Submission Proof - C:\Users\m158328\AppData\Local\Temp\SECPub.temp\Publish\etfnq093023


	Schedule of Investments
	Principal Active High Yield ETF
	September 30, 2023 (unaudited)

		Principal
BONDS — 89.29%		Amount		Value

Aerospace & Defense — 1.84%
Bombardier, Inc.
7.50%, 02/01/2029 ^(a),(b)	$	585,000	$	555,145
Triumph Group, Inc.
7.75%, 08/15/2025 ^(b)		1,499,000		1,424,050
			$	1,979,195

Airlines — 0.06%
United Airlines 2016-1 Class B Pass-Through Trust
3.65%, 07/07/2027		69,291		64,882

Auto Manufacturers — 1.73%
Ford Motor Co.
3.25%, 02/12/2032		904,000		696,680
Ford Motor Credit Co. LLC
3.38%, 11/13/2025		976,000		905,548
4.54%, 08/01/2026		269,000		252,514
			$	1,854,742

Auto Parts & Equipment — 1.43%
Dana, Inc.
4.25%, 09/01/2030		1,264,000		1,014,487
Tenneco, Inc.
8.00%, 11/17/2028 ^(a)		635,000		516,731
			$	1,531,218

Banks — 1.42%
JPMorgan Chase & Co.
(3-month Term Secured Overnight Financing Rate + 3.13%),
4.60%, 02/01/2025 ^(c),(d)		1,629,000		1,523,912

Building Materials — 2.50%
AmeriTex HoldCo Intermediate LLC
10.25%, 10/15/2028		1,010,000		998,637
Smyrna Ready Mix Concrete LLC
6.00%, 11/01/2028 ^(a)		1,826,000		1,686,240
			$	2,684,877

Chemicals — 4.10%
Consolidated Energy Finance SA
5.63%, 10/15/2028 ^(a)		1,172,000		968,365
Kobe U.S. Midco 2, Inc.
9.25%, PIK 10.00%; 11/01/2026 ^(a),(e)		1,679,000		1,225,670
Olympus Water U.S. Holding Corp.
6.25%, 10/01/2029 ^(a),(b)		1,982,000		1,531,526
Tronox, Inc.
4.63%, 03/15/2029 ^(a)		837,000		675,464
			$	4,401,025

Commercial Services — 3.96%
Albion Financing 1 SARL/Aggreko Holdings, Inc.
6.13%, 10/15/2026 ^(a)		1,017,000		960,546
Garda World Security Corp.
6.00%, 06/01/2029 ^(a)		194,000		158,671
9.50%, 11/01/2027 ^(a)		1,043,000		997,229
WASH Multifamily Acquisition, Inc.
5.75%, 04/15/2026 ^(a)		1,396,000		1,303,515

See accompanying notes.


Schedule of Investments
Principal Active High Yield ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Commercial Services (continued)
ZipRecruiter, Inc.
5.00%, 01/15/2030 ^(a)	$	1,060,000	$	832,117
			$	4,252,078

Computers — 1.44%
Seagate HDD Cayman
5.75%, 12/01/2034		645,000		544,784
9.63%, 12/01/2032 ^(a)		931,159		1,003,363
			$	1,548,147

Diversified Financial Services — 6.99%
AerCap Holdings NV
(5-year Treasury Constant Maturity Rate + 4.54%),
5.88%, 10/10/2079 ^(c)		1,751,000		1,702,800
Credit Acceptance Corp.
6.63%, 03/15/2026 ^(b)		1,522,000		1,467,344
Global Aircraft Leasing Co. Ltd.
6.50%, PIK 7.25%; 09/15/2024 ^(a),(e)		1,564,004		1,489,714
Macquarie Airfinance Holdings Ltd.
8.13%, 03/30/2029		460,000		460,621
8.38%, 05/01/2028 ^(a)		987,000		1,000,571
OneMain Finance Corp.
3.50%, 01/15/2027		133,000		113,881
4.00%, 09/15/2030		1,393,000		1,045,245
6.63%, 01/15/2028		250,000		230,667
			$	7,510,843

Electric — 4.24%
Clearway Energy Operating LLC
3.75%, 02/15/2031 ^(a)		1,898,000		1,497,140
GenOn Energy, Inc.
0.00%, 10/15/2020 ^(f),(g),(h)		3,100,000		—
NRG Energy, Inc.
3.88%, 02/15/2032 ^(a)		1,539,000		1,155,312
(5-year Treasury Constant Maturity Rate + 5.92%),
10.25%, 03/15/2028 ^(a),(c),(d)		233,000		228,201
Vistra Corp.
(5-year Treasury Constant Maturity Rate + 5.74%),
7.00%, 12/15/2026 ^(a),(c),(d)		715,000		652,438
Vistra Operations Co. LLC
4.38%, 05/01/2029 ^(a)		1,184,000		1,017,804
			$	4,550,895

Electronics — 1.04%
Sensata Technologies BV
4.00%, 04/15/2029 ^(a)		155,000		133,470
Sensata Technologies, Inc.
3.75%, 02/15/2031 ^(a)		1,214,000		982,521
			$	1,115,991

Entertainment — 7.29%
Boyne USA, Inc.
4.75%, 05/15/2029 ^(a)		1,859,000		1,625,984
CCM Merger, Inc.
6.38%, 05/01/2026 ^(a)		1,631,000		1,560,003

See accompanying notes.


	Schedule of Investments
	Principal Active High Yield ETF
	September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Entertainment (continued)
CDI Escrow Issuer, Inc.
5.75%, 04/01/2030 ^(a)	$	1,653,000	$	1,493,351
Cinemark USA, Inc.
5.25%, 07/15/2028 ^(a)		1,406,000		1,248,050
International Game Technology PLC
5.25%, 01/15/2029 ^(a)		1,059,000		975,880
Lions Gate Capital Holdings LLC
5.50%, 04/15/2029 ^(a)		1,412,000		930,941
			$	7,834,209

Food — 3.11%
Albertsons Cos., Inc./Safeway, Inc./New Albertsons LP/Albertsons LLC
3.50%, 03/15/2029 ^(a)		1,027,000		875,605
Chobani LLC/Chobani Finance Corp., Inc.
7.50%, 04/15/2025 ^(a)		1,160,000		1,149,073
Pilgrim's Pride Corp.
3.50%, 03/01/2032		1,508,000		1,166,140
4.25%, 04/15/2031		183,000		152,659
			$	3,343,477

Forest Products & Paper — 0.58%
Mercer International, Inc.
5.13%, 02/01/2029		726,000		572,460
12.88%, 10/01/2028		55,000		55,602
			$	628,062

Healthcare — Services — 2.54%
Acadia Healthcare Co., Inc.
5.00%, 04/15/2029 ^(a)		1,616,000		1,452,929
Tenet Healthcare Corp.
6.13%, 06/15/2030		1,361,000		1,276,005
			$	2,728,934

Home Builders — 2.02%
Adams Homes, Inc.
9.25%, 10/15/2028		665,000		663,969
Forestar Group, Inc.
3.85%, 05/15/2026 ^(a)		268,000		243,261
5.00%, 03/01/2028 ^(a)		1,404,000		1,260,434
			$	2,167,664

Household Products/Wares — 0.99%
Kronos Acquisition Holdings, Inc./KIK Custom Products, Inc.
5.00%, 12/31/2026 ^(a)		1,165,000		1,061,451

Insurance — 0.77%
Acrisure LLC/Acrisure Finance, Inc.
4.25%, 02/15/2029 ^(a)		187,000		157,137
7.00%, 11/15/2025 ^(a)		693,000		673,111
			$	830,248

Investment Companies — 1.10%
Compass Group Diversified Holdings LLC
5.25%, 04/15/2029 ^(a)		1,037,000		906,637

See accompanying notes.


Schedule of Investments
Principal Active High Yield ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Investment Companies (continued)
Icahn Enterprises LP/Icahn Enterprises Finance Corp.
4.38%, 02/01/2029	$	340,000	$	271,884
			$	1,178,521

Iron & Steel — 0.61%
TMS International Corp.
6.25%, 04/15/2029 ^(a)		796,000		658,296

Leisure Time — 1.50%
Life Time, Inc.
5.75%, 01/15/2026 ^(a)		1,658,000		1,606,576

Lodging — 1.60%
Wynn Las Vegas LLC/Wynn Las Vegas Capital Corp.
5.25%, 05/15/2027 ^(a)		1,096,000		1,019,494
Wynn Macau Ltd.
5.63%, 08/26/2028 ^(a)		812,000		703,966
			$	1,723,460

Machinery — Diversified — 1.31%
Maxim Crane Works Holdings Capital LLC
11.50%, 09/01/2028		1,440,000		1,402,200

Media — 6.60%
CCO Holdings LLC/CCO Holdings Capital Corp.
4.25%, 02/01/2031 ^(a)		1,638,000		1,303,911
4.75%, 02/01/2032 ^(a)		520,000		416,000
Directv Financing LLC/Directv Financing Co.-Obligor, Inc.
5.88%, 08/15/2027 ^(a)		1,618,000		1,430,603
DISH DBS Corp.
5.13%, 06/01/2029		184,000		102,006
5.25%, 12/01/2026 ^(a)		13,284		11,289
7.38%, 07/01/2028		837,000		527,385
DISH Network Corp.
11.75%, 11/15/2027 ^(a)		1,183,000		1,191,832
Scripps Escrow II, Inc.
5.38%, 01/15/2031 ^(a)		516,000		317,056
Sirius XM Radio, Inc.
3.13%, 09/01/2026 ^(a)		1,398,000		1,245,967
UPC Holding BV
5.50%, 01/15/2028 ^(a)		609,000		540,488
			$	7,086,537

Mining — 3.10%
Copper Mountain Mining Corp.
8.00%, 04/09/2026 ^(a)		989,734		999,631
Novelis Corp.
3.88%, 08/15/2031 ^(a)		946,000		755,461
Taseko Mines Ltd.
7.00%, 02/15/2026 ^(a)		1,686,000		1,574,943
			$	3,330,035

Oil & Gas — 4.40%
Aethon United BR LP/Aethon United Finance Corp.
8.25%, 02/15/2026 ^(a)		1,386,000		1,375,064
Comstock Resources, Inc.
5.88%, 01/15/2030 ^(a)		1,544,000		1,336,533

See accompanying notes.


Schedule of Investments
Principal Active High Yield ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Oil & Gas (continued)
MEG Energy Corp.
7.13%, 02/01/2027 ^(a)	$	972,000	$	985,468
Southwestern Energy Co.
4.75%, 02/01/2032		1,197,000		1,027,371
			$	4,724,436

Oil & Gas Services — 0.91%
Archrock Partners LP/Archrock Partners Finance Corp.
6.25%, 04/01/2028 ^(a)		1,050,000		977,576

Packaging & Containers — 1.59%
Clydesdale Acquisition Holdings, Inc.
6.63%, 04/15/2029 ^(a)		156,000		145,047
8.75%, 04/15/2030 ^(a)		593,000		508,592
LABL, Inc.
5.88%, 11/01/2028 ^(a)		302,000		271,111
8.25%, 11/01/2029 ^(a)		485,000		395,881
9.50%, 11/01/2028 ^(a)		377,000		386,425
			$	1,707,056

Pharmaceuticals — 3.10%
AdaptHealth LLC
5.13%, 03/01/2030 ^(a)		1,267,000		981,136
BellRing Brands, Inc.
7.00%, 03/15/2030 ^(a)		916,000		901,948
Jazz Securities DAC
4.38%, 01/15/2029 ^(a)		1,654,000		1,442,096
			$	3,325,180

Pipelines — 6.96%
Antero Midstream Partners LP/Antero Midstream Finance Corp.
5.38%, 06/15/2029 ^(a)		940,000		860,652
5.75%, 03/01/2027 ^(a)		611,000		583,171
CNX Midstream Partners LP
4.75%, 04/15/2030 ^(a)		1,156,000		962,243
Crestwood Midstream Partners LP/Crestwood Midstream Finance Corp.
5.63%, 05/01/2027 ^(a)		1,255,000		1,202,838
DT Midstream, Inc.
4.13%, 06/15/2029 ^(a)		730,000		631,480
Hess Midstream Operations LP
4.25%, 02/15/2030 ^(a)		1,147,000		967,194
Kinetik Holdings LP
5.88%, 06/15/2030 ^(a)		1,225,000		1,148,438
Venture Global Calcasieu Pass LLC
3.88%, 11/01/2033 ^(a)		1,314,000		1,020,223
Venture Global LNG, Inc.
8.38%, 06/01/2031 ^(a)		96,000		94,374
			$	7,470,613

REITs — 2.27%
CBL & Associates LP
0.00%, 12/15/2026 ^(f),(g),(h)		6,000,000		—
HAT Holdings I LLC/HAT Holdings II LLC
3.38%, 06/15/2026 ^(a)		888,000		789,284
3.75%, 09/15/2030 ^(a)		203,000		155,350

See accompanying notes.


Schedule of Investments
Principal Active High Yield ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

REITs (continued)
Ladder Capital Finance Holdings LLLP/Ladder Capital Finance Corp.
4.75%, 06/15/2029 ^(a)	$	1,846,000	$	1,491,208
			$	2,435,842

Retail — 3.53%
Bath & Body Works, Inc.
5.25%, 02/01/2028		320,000		296,145
6.63%, 10/01/2030 ^(a)		535,000		501,568
6.75%, 07/01/2036		281,000		246,198
9.38%, 07/01/2025 ^(a)		30,000		31,203
Fertitta Entertainment LLC/Fertitta Entertainment Finance Co., Inc.
4.63%, 01/15/2029 ^(a)		713,000		604,267
6.75%, 01/15/2030 ^(a)		488,000		397,769
LSF9 Atlantis Holdings LLC/Victra Finance Corp.
7.75%, 02/15/2026 ^(a)		1,040,000		944,312
Park River Holdings, Inc.
5.63%, 02/01/2029 ^(a)		605,000		461,295
Patrick Industries, Inc.
4.75%, 05/01/2029 ^(a)		374,000		312,290
			$	3,795,047

Software — 1.42%
Open Text Corp.
3.88%, 12/01/2029 ^(a)		1,860,000		1,528,954

Telecommunications — 0.17%
Level 3 Financing, Inc.
10.50%, 05/15/2030 ^(a)		180,000		181,186

Transportation — 1.07%
Watco Cos. LLC/Watco Finance Corp.
6.50%, 06/15/2027 ^(a)		1,216,000		1,154,835
TOTAL BONDS			$	95,898,200
		Principal
SENIOR FLOATING RATE INTERESTS — 7.05%		Amount		Value

Airlines — 2.89%
AAdvantage Loyalty IP Ltd., 2021 Term Loan B
(3-month Term Secured Overnight Financing Rate + 4.75%),
10.34%, 04/20/2028	$	1,287,250	$	1,324,580
United Airlines, Inc., 2021 Term Loan B
(1-month Term Secured Overnight Financing Rate + 3.75%),
9.18%, 04/21/2028		1,781,541		1,781,951
			$	3,106,531

Auto Parts & Equipment — 0.18%
Tenneco, Inc., 2022 Term Loan B
(3-month Term Secured Overnight Financing Rate + 5.00%),
10.48%-10.49%, 11/17/2028		225,000		190,519

Forest Products & Paper — 1.23%
Spectrum Group Buyer, Inc., 2022 Term Loan B
(3-month Term Secured Overnight Financing Rate + 6.50%),
11.95%, 05/19/2028		1,377,111		1,323,059




See accompanying notes.	6


	Schedule of Investments
	Principal Active High Yield ETF

	September 30, 2023 (unaudited)
			Principal
SENIOR FLOATING RATE INTERESTS (continued)			Amount		Value

Healthcare — Products — 0.91%
Medline Borrower LP, USD Term Loan B
	(1-month Term Secured Overnight Financing Rate + 3.25%),
	8.68%, 10/23/2028	$	980,025	$	976,791

Healthcare — Services — 1.00%
Star Parent, Inc., 2023 Term Loan B
	0.00%, 09/19/2030 ⁽ⁱ⁾		1,100,000		1,074,183

Mining — 0.84%
Arsenal AIC Parent LLC
	(3-month Term Secured Overnight Financing Rate + 4.50%),
	9.88%, 08/18/2030		905,000		902,357
TOTAL SENIOR FLOATING RATE INTERESTS				$	7,573,440
U.S. GOVERNMENT & GOVERNMENT AGENCY OBLIGATIONS —			Principal
1.40%			Amount		Value

U.S. Treasury — 1.40%
	3.50%, 04/30/2028	$	1,583,200	$	1,508,988
TOTAL U.S. GOVERNMENT & GOVERNMENT AGENCY OBLIGATIONS				$	1,508,988
INVESTMENT COMPANIES — 4.23%			Shares Held		Value

Money Market Funds — 4.23%
Principal Government Money Market Fund — Class R-6 5.26% ^(j),(k),(l)			2,664,463	$	2,664,463
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(l)			1,880,497		1,880,497
TOTAL INVESTMENT COMPANIES				$	4,544,960
Total Investments				$	109,525,588
Other Assets and Liabilities — (1.97)%					(2,119,556	)

Total Net Assets — 100.00%				$	107,406,032

^(a)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in
	transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these
	securities totaled $75,692,124 or 70.47% of net assets.
^(b)	Security or a portion of the security was on loan. At the end of the period, the value of these securities totaled $2,622,420 or
	2.44% of net assets.
^(c)	Rate shown is as of period end. The rate may be a variable or floating rate or a fixed rate which may convert to a variable or
	floating rate in the future.
^(d)	Perpetual security. Perpetual securities pay an indefinite stream of interest, but they may be called by the issuer at an earlier
	date. Date shown, if any, reflects the next call date or final legal maturity date. Rate shown is as of period end.
^(e)	Payment in kind; the issuer has the option of paying additional securities in lieu of cash.
^(f)	Non-income producing security.
^(g)	The value of these investments was determined using significant unobservable inputs, in good faith by the Advisor, under
	procedures established and periodically reviewed by the Board of Trustees.
^(h)	Security is defaulted.
⁽ⁱ⁾	This Senior Floating Rate Interest will settle after September 30, 2023, at which time the interest rate will be determined.
^(j)	Affiliated Security. Security is either an affiliate (and registered under the Investment Company Act of 1940) or an affiliate
	as defined by the Investment Company Act of 1940 (controls 5.00% or more of the outstanding voting shares of the security).
	Please see Affiliated Securities sub-schedule for transactional information.
^(k)	Security or a portion of the security was received as collateral for securities lending. At the end of the period, the value of
	these securities totaled $2,664,463 or 2.48% of net assets.
^(l)	1-day yield shown as of period end.




See accompanying notes.		7


		Schedule of Investments
		Principal Active High Yield ETF
		September 30, 2023 (unaudited)

Portfolio Summary
Sector			Percent
Consumer, Cyclical				22.23	%
Consumer, Non-cyclical				15.61	%
Financial				12.55	%
Energy				12.26	%
Basic Materials				10.47	%
Industrial				9.35	%
Communications				6.77	%
Utilities				4.24	%
Money Market Funds				4.23	%
Technology				2.86	%
Government				1.40	%
Other Assets and Liabilities				(1.97	)%
TOTAL NET ASSETS				100.00	%

		June 30, 2023	Purchases				Sales		September 30, 2023
Affiliated Securities		Value		Cost			Proceeds		Value
Principal Government Money
Market Fund — Class R-6 5.26%	$	3,219,013	$	3,711,865		$	4,266,415	$	2,664,463
	$	3,219,013	$	3,711,865		$	4,266,415	$	2,664,463

						Realized Gain
				Realized			from		Change in
			Gain/(Loss) on			Capital Gain			Unrealized
		Income ^(a)	Investments			Distributions			Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%	$	—	$	—		$	—	$	—
	$	—	$	—		$	—	$	—

^(a)Amount excludes earnings from securities lending collateral.

See accompanying notes.


	Schedule of Investments
	Principal Focused Blue Chip ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.79%		Shares Held		Value
Aerospace & Defense — 4.50%
TransDigm Group, Inc. ^(a)		366	$	308,585
Commercial Services — 8.61%
CoStar Group, Inc. ^(a)		3,027		232,746
Moody's Corp.		621		196,342
S&P Global, Inc.		442		161,511
			$	590,599
Diversified Financial Services — 13.39%
Charles Schwab Corp.		1,703		93,495
Mastercard, Inc., Class A		1,289		510,328
Visa, Inc., Class A		1,365		313,963
			$	917,786
Healthcare — Products — 4.59%
Danaher Corp.		1,268		314,591
Insurance — 4.12%
Progressive Corp.		2,026		282,222
Internet — 24.05%
Alphabet, Inc., Class C ^(a)		6,336		835,402
Amazon.com, Inc. ^(a)		5,737		729,287
Netflix, Inc. ^(a)		224		84,582
			$	1,649,271
Lodging — 2.62%
Hilton Worldwide Holdings, Inc.		1,198		179,916
Pharmaceuticals — 1.44%
Zoetis, Inc.		566		98,473
Private Equity — 4.51%
Brookfield Corp., Class A		9,888		309,198
REITs — 3.05%
American Tower Corp.		1,270		208,851
Retail — 1.74%
O'Reilly Automotive, Inc. ^(a)		131		119,061
Software — 24.21%
Adobe, Inc. ^(a)		619		315,628
Intuit, Inc.		482		246,273
Microsoft Corp.		2,900		915,675
Roper Technologies, Inc.		377		182,574
			$	1,660,150
Transportation — 2.96%
Union Pacific Corp.		998		203,223
TOTAL COMMON STOCKS			$	6,841,926
INVESTMENT COMPANIES — 0.16%		Shares Held		Value
Money Market Fund — 0.16%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)		10,641	$	10,641
TOTAL INVESTMENT COMPANIES			$	10,641




See accompanying notes.	9


	Schedule of Investments
	Principal Focused Blue Chip ETF
	September 30, 2023 (unaudited)

Total Investments		$	6,852,567
Other Assets and Liabilities — 0.05%			3,736
Total Net Assets — 100.00%		$	6,856,303

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.


Portfolio Summary

Sector	Percent
Financial	25.06	%
Technology	24.21	%
Communications	24.06	%
Consumer, Non-cyclical	14.64	%
Industrial	7.46	%
Consumer, Cyclical	4.36	%
Money Market Fund	0.16	%
Other Assets and Liabilities	0.05	%
TOTAL NET ASSETS	100.00	%

See accompanying notes.


	Schedule of Investments
	Principal Healthcare Innovators ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.81%		Shares Held		Value

Biotechnology — 64.60%
2seventy bio, Inc. ^(a),(b)		9,209	$	36,099
4D Molecular Therapeutics, Inc. ^(a)		5,429		69,111
Aadi Bioscience, Inc. ^(a)		6,869		33,246
ACADIA Pharmaceuticals, Inc. ^(a)		21,232		442,475
Adicet Bio, Inc. ^(a)		9,296		12,736
ADMA Biologics, Inc. ^(a)		35,441		126,879
Aerovate Therapeutics, Inc. ^(a)		4,552		61,771
Agenus, Inc. ^(a)		57,432		64,898
Akero Therapeutics, Inc. ^(a)		6,365		321,942
Allogene Therapeutics, Inc. ^(a)		23,163		73,427
Allovir, Inc. ^(a)		18,369		39,493
Alnylam Pharmaceuticals, Inc. ^(a)		8,267		1,464,086
Amicus Therapeutics, Inc. ^(a)		37,169		451,975
AnaptysBio, Inc. ^(a)		4,672		83,909
Anavex Life Sciences Corp. ^(a),(b)		13,257		86,833
ANI Pharmaceuticals, Inc. ^(a)		2,892		167,909
Apellis Pharmaceuticals, Inc. ^(a)		14,269		542,793
Arbutus Biopharma Corp. ^(a),(b)		29,854		60,604
Arcellx, Inc. ^(a)		6,502		233,292
Arcturus Therapeutics Holdings, Inc. ^(a)		4,322		110,427
Arcus Biosciences, Inc. ^(a)		10,287		184,652
Arcutis Biotherapeutics, Inc. ^(a)		9,667		51,332
Arrowhead Pharmaceuticals, Inc. ^(a)		14,150		380,210
Atara Biotherapeutics, Inc. ^(a)		21,618		31,995
Atea Pharmaceuticals, Inc. ^(a)		19,793		59,379
Aurinia Pharmaceuticals, Inc. ^(a)		19,956		155,058
Avidity Biosciences, Inc. ^(a)		10,464		66,760
Axsome Therapeutics, Inc. ^(a)		5,706		398,792
Beam Therapeutics, Inc. ^(a)		9,774		235,065
Bio-Rad Laboratories, Inc., Class A ^(a)		3,604		1,291,854
BioCryst Pharmaceuticals, Inc. ^(a)		26,668		188,809
Biohaven Ltd. ^(a)		10,281		267,409
Bluebird Bio, Inc. ^(a)		21,994		66,862
Blueprint Medicines Corp. ^(a)		7,910		397,240
Bridgebio Pharma, Inc. ^(a)		22,108		582,988
C4 Therapeutics, Inc. ^(a)		13,917		25,886
Cara Therapeutics, Inc. ^(a)		12,807		21,516
Caribou Biosciences, Inc. ^(a)		14,197		67,862
Cassava Sciences, Inc. ^(a),(b)		6,364		105,897
Celldex Therapeutics, Inc. ^(a)		6,496		178,770
Cerevel Therapeutics Holdings, Inc. ^(a)		20,164		440,180
Chinook Therapeutics, Inc. ^(a),(c)		9,493		3,797
Cogent Biosciences, Inc. ^(a)		11,197		109,171
Crinetics Pharmaceuticals, Inc. ^(a)		8,250		245,355
Cullinan Oncology, Inc. ^(a)		7,509		67,956
Cytokinetics, Inc. ^(a)		12,360		364,126
Day One Biopharmaceuticals, Inc. ^(a)		11,054		135,633
Deciphera Pharmaceuticals, Inc. ^(a)		11,277		143,443
Denali Therapeutics, Inc. ^(a)		17,823		367,688
Design Therapeutics, Inc. ^(a)		11,833		27,926
Dyne Therapeutics, Inc. ^(a)		9,516		85,263
Edgewise Therapeutics, Inc. ^(a)		11,541		66,130
Editas Medicine, Inc. ^(a)		12,086		94,271
Emergent BioSolutions, Inc. ^(a)		8,300		28,220
EQRx, Inc. ^(a)		75,666		167,978
Erasca, Inc. ^(a)		29,471		58,058
Esperion Therapeutics, Inc. ^(a)		34,436		33,747
Evolus, Inc. ^(a)		10,191		93,146

See accompanying notes.


	Schedule of Investments
	Principal Healthcare Innovators ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Biotechnology (continued)
Fate Therapeutics, Inc. ^(a)		16,639	$	35,275
FibroGen, Inc. ^(a)		12,359		10,665
Geron Corp. ^(a)		72,324		153,327
Gossamer Bio, Inc. ^(a),(b)		33,504		27,902
Ideaya Biosciences, Inc. ^(a)		7,825		211,118
IGM Biosciences, Inc. ^(a),(b)		6,221		51,945
Illumina, Inc. ^(a)		7,599		1,043,191
ImmunityBio, Inc. ^(a),(b)		64,285		108,642
ImmunoGen, Inc. ^(a)		34,589		548,927
Immunovant, Inc. ^(a)		17,789		682,920
Inhibrx, Inc. ^(a)		6,724		123,385
Inovio Pharmaceuticals, Inc. ^(a),(b)		61,331		23,858
Insmed, Inc. ^(a)		18,247		460,737
Intellia Therapeutics, Inc. ^(a)		11,517		364,168
Intercept Pharmaceuticals, Inc. ^(a)		6,798		126,035
Intra-Cellular Therapies, Inc. ^(a)		12,069		628,674
Ionis Pharmaceuticals, Inc. ^(a)		18,201		825,597
Iovance Biotherapeutics, Inc. ^(a)		32,158		146,319
Karuna Therapeutics, Inc. ^(a)		4,659		787,790
Karyopharm Therapeutics, Inc. ^(a),(b)		19,466		26,084
Keros Therapeutics, Inc. ^(a)		4,143		132,079
Kezar Life Sciences, Inc. ^(a)		19,058		22,679
Kiniksa Pharmaceuticals Ltd., Class A ^(a)		6,827		118,585
Kodiak Sciences, Inc. ^(a)		11,695		21,051
Krystal Biotech, Inc. ^(a)		3,496		405,536
Kymera Therapeutics, Inc. ^(a)		7,580		105,362
Ligand Pharmaceuticals, Inc. ^(a)		2,468		147,883
Liquidia Corp. ^(a)		12,024		76,232
MacroGenics, Inc. ^(a)		12,003		55,934
Mersana Therapeutics, Inc. ^(a)		18,957		24,075
Mineralys Therapeutics, Inc. ^(a)		7,094		67,464
Mirati Therapeutics, Inc. ^(a)		7,767		338,330
Myriad Genetics, Inc. ^(a)		11,113		178,252
Nektar Therapeutics ^(a)		57,793		34,421
NGM Biopharmaceuticals, Inc. ^(a)		15,993		17,112
Nkarta, Inc. ^(a)		11,294		15,699
Novavax, Inc. ^(a),(b)		13,964		101,099
Nurix Therapeutics, Inc. ^(a)		8,529		67,038
Nuvalent, Inc., Class A ^(a)		7,110		326,847
Phathom Pharmaceuticals, Inc. ^(a),(b)		7,853		81,436
Point Biopharma Global, Inc. ^(a)		16,600		110,722
Praxis Precision Medicines, Inc. ^(a)		34,652		59,255
Precigen, Inc. ^(a),(b)		55,832		79,281
Prime Medicine, Inc. ^(a),(b)		13,874		132,358
Prothena Corp. PLC ^(a)		6,946		335,144
PTC Therapeutics, Inc. ^(a)		9,524		213,433
RAPT Therapeutics, Inc. ^(a)		5,700		94,734
Recursion Pharmaceuticals, Inc., Class A ^(a)		27,596		211,109
REGENXBIO, Inc. ^(a)		6,872		113,113
Relay Therapeutics, Inc. ^(a)		17,094		143,761
Replimune Group, Inc. ^(a)		8,635		147,745
REVOLUTION Medicines, Inc. ^(a)		13,980		386,966
Rigel Pharmaceuticals, Inc. ^(a)		46,545		50,269
Rocket Pharmaceuticals, Inc. ^(a)		11,173		228,935
Sage Therapeutics, Inc. ^(a)		7,898		162,541
Sana Biotechnology, Inc. ^(a)		29,054		112,439
Sangamo Therapeutics, Inc. ^(a)		35,574		21,337
Sarepta Therapeutics, Inc. ^(a)		10,934		1,325,419

See accompanying notes.


	Schedule of Investments
	Principal Healthcare Innovators ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Biotechnology (continued)
Scilex Holding Co. ^(a)		10,078	$	14,109
Seagen, Inc. ^(a)		8,489		1,800,941
Seer, Inc. ^(a)		15,152		33,486
SpringWorks Therapeutics, Inc. ^(a)		8,747		202,231
Stoke Therapeutics, Inc. ^(a),(b)		8,460		33,332
Sutro Biopharma, Inc. ^(a)		13,701		47,542
Syndax Pharmaceuticals, Inc. ^(a)		9,719		141,120
TG Therapeutics, Inc. ^(a)		19,163		160,203
Theravance Biopharma, Inc. ^(a)		10,325		89,105
Theseus Pharmaceuticals, Inc. ^(a)		8,532		22,951
Travere Therapeutics, Inc. ^(a)		10,303		92,109
Twist Bioscience Corp. ^(a)		9,014		182,624
Ultragenyx Pharmaceutical, Inc. ^(a)		9,254		329,905
Ventyx Biosciences, Inc. ^(a)		7,890		274,020
Vera Therapeutics, Inc. ^(a)		9,636		132,110
Veracyte, Inc. ^(a)		10,081		225,109
Vericel Corp. ^(a)		6,664		223,377
Verve Therapeutics, Inc. ^(a)		9,310		123,451
Vir Biotechnology, Inc. ^(a)		17,401		163,047
Viridian Therapeutics, Inc. ^(a)		6,236		95,660
Xencor, Inc. ^(a)		8,264		166,520
Zentalis Pharmaceuticals, Inc. ^(a)		8,559		171,694
			$	29,151,209

Chemicals — 0.06%
Codexis, Inc. ^(a)		13,853		26,182

Healthcare — Products — 22.13%
10X Genomics, Inc., Class A ^(a)		12,375		510,469
Adaptive Biotechnologies Corp. ^(a)		20,938		114,112
Alphatec Holdings, Inc. ^(a)		15,374		199,401
AngioDynamics, Inc. ^(a)		8,091		59,145
Artivion, Inc. ^(a)		6,895		104,528
AtriCure, Inc. ^(a)		6,384		279,619
Axogen, Inc. ^(a)		8,685		43,425
Axonics, Inc. ^(a)		6,578		369,157
Azenta, Inc. ^(a)		9,106		457,030
BioLife Solutions, Inc. ^(a)		6,627		91,519
Bionano Genomics, Inc. ^(a),(b)		7,632		23,125
Butterfly Network, Inc. ^(a),(b)		34,762		41,019
CareDx, Inc. ^(a)		9,906		69,342
Cerus Corp. ^(a)		33,432		54,160
Cutera, Inc. ^(a)		3,462		20,841
Exact Sciences Corp. ^(a)		22,118		1,508,890
Glaukos Corp. ^(a)		6,432		484,008
ICU Medical, Inc. ^(a)		3,085		367,146
Inari Medical, Inc. ^(a)		7,045		460,743
Inogen, Inc. ^(a)		4,646		24,252
Inspire Medical Systems, Inc. ^(a)		3,642		722,718
iRhythm Technologies, Inc. ^(a)		3,891		366,766
MaxCyte, Inc. ^(a)		18,348		57,246
MiMedx Group, Inc. ^(a)		21,927		159,848
NanoString Technologies, Inc. ^(a)		8,034		13,818
Natera, Inc. ^(a)		14,323		633,793
Nevro Corp. ^(a)		5,236		100,636
Novocure Ltd. ^(a)		13,304		214,860
OmniAb, Inc. ^(a)		21,853		113,417
OmniAb, Inc., Earnout Shares ^(a)		977		—
OmniAb, Inc., Earnout Shares ^(a)		977		—

See accompanying notes.


	Schedule of Investments
	Principal Healthcare Innovators ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Healthcare — Products (continued)
Orthofix Medical, Inc. ^(a)		5,951	$	76,530
OrthoPediatrics Corp. ^(a)		3,412		109,184
Pacific Biosciences of California, Inc. ^(a)		32,791		273,805
Paragon 28, Inc. ^(a)		12,347		154,955
PROCEPT BioRobotics Corp. ^(a)		6,218		204,013
Pulmonx Corp. ^(a)		6,918		71,463
Quanterix Corp. ^(a)		6,858		186,126
Quantum-Si, Inc. ^(a),(b)		33,879		56,239
RxSight, Inc. ^(a)		5,812		162,097
SI-BONE, Inc. ^(a)		5,623		119,432
Silk Road Medical, Inc. ^(a)		5,333		79,942
SomaLogic, Inc. ^(a)		33,251		79,470
Surmodics, Inc. ^(a)		2,939		94,312
Tactile Systems Technology, Inc. ^(a)		4,325		60,766
Tandem Diabetes Care, Inc. ^(a)		8,853		183,877
TransMedics Group, Inc. ^(a)		4,256		233,016
Treace Medical Concepts, Inc. ^(a)		8,585		112,549
Zimvie, Inc. ^(a)		6,804		64,026
			$	9,986,835

Healthcare — Services — 0.22%
Inotiv, Inc. ^(a),(b)		7,668		23,618
Nano-X Imaging Ltd. ^(a),(b)		11,286		74,036
			$	97,654

Pharmaceuticals — 12.40%
AbCellera Biologics, Inc. ^(a),(b)		38,695		177,997
Aclaris Therapeutics, Inc. ^(a)		11,443		78,385
Agios Pharmaceuticals, Inc. ^(a)		7,964		197,109
Alector, Inc. ^(a)		14,646		94,906
Alkermes PLC ^(a)		21,018		588,714
Amneal Pharmaceuticals, Inc. ^(a)		36,400		153,608
Amylyx Pharmaceuticals, Inc. ^(a)		8,994		164,680
Anika Therapeutics, Inc. ^(a)		2,908		54,176
Arvinas, Inc. ^(a)		7,518		147,654
Bioxcel Therapeutics, Inc. ^(a),(b)		4,849		12,268
Coherus Biosciences, Inc. ^(a)		13,326		49,839
Collegium Pharmaceutical, Inc. ^(a)		5,454		121,897
Elanco Animal Health, Inc. ^(a)		62,800		705,872
Enanta Pharmaceuticals, Inc. ^(a)		3,364		37,576
Fulcrum Therapeutics, Inc. ^(a)		18,749		83,246
Heron Therapeutics, Inc. ^(a),(b)		23,433		24,136
KalVista Pharmaceuticals, Inc. ^(a)		7,894		76,019
Kura Oncology, Inc. ^(a)		11,073		100,986
Lyell Immunopharma, Inc. ^(a)		43,451		63,873
Madrigal Pharmaceuticals, Inc. ^(a)		2,305		336,622
MannKind Corp. ^(a)		39,083		161,413
Mirum Pharmaceuticals, Inc. ^(a)		5,730		181,068
Morphic Holding, Inc. ^(a)		5,482		125,593
Ocugen, Inc. ^(a),(b)		61,761		24,704
Ocular Therapeutix, Inc. ^(a)		14,131		44,371
Perrigo Co. PLC		17,259		551,425
PMV Pharmaceuticals, Inc. ^(a)		11,966		73,471
Protagonist Therapeutics, Inc. ^(a)		8,104		135,175
Revance Therapeutics, Inc. ^(a)		11,005		126,227
Senseonics Holdings, Inc. ^(a)		106,283		64,184
Seres Therapeutics, Inc. ^(a)		19,137		45,546
SIGA Technologies, Inc.		14,515		76,204

See accompanying notes.


		Schedule of Investments
		Principal Healthcare Innovators ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)				Shares Held		Value

Pharmaceuticals (continued)
Vaxcyte, Inc. ^(a)				11,830	$	603,093
Xeris Biopharma Holdings, Inc. ^(a)				29,583		55,024
Y-mAbs Therapeutics, Inc. ^(a)				10,457		56,991
					$	5,594,052

Software — 0.18%
Outset Medical, Inc. ^(a)				7,587		82,546
Transportation — 0.22%
CryoPort, Inc. ^(a)				7,225		99,055
TOTAL COMMON STOCKS					$	45,037,533
INVESTMENT COMPANIES — 2.65%				Shares Held		Value

Money Market Funds — 2.65%
Principal Government Money Market Fund — Class R-6 5.26% ^(d),(e),(f)				1,098,477	$	1,098,477
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(f)				97,526		97,526
TOTAL INVESTMENT COMPANIES					$	1,196,003
Total Investments					$	46,233,536
Other Assets and Liabilities — (2.46)%						(1,111,585	)
Total Net Assets — 100.00%					$	45,121,951

^(a)	Non-income producing security.
^(b)	Security or a portion of the security was on loan. At the end of the period, the value of these securities totaled $969,035 or
	2.15% of net assets.
^(c)	The value of these investments was determined using significant unobservable inputs, in good faith by the Advisor, under
	procedures established and periodically reviewed by the Board of Trustees.
^(d)	Affiliated Security. Security is either an affiliate (and registered under the Investment Company Act of 1940) or an affiliate
	as defined by the Investment Company Act of 1940 (controls 5.00% or more of the outstanding voting shares of the security).
	Please see Affiliated Securities sub-schedule for transactional information.
^(e)	Security or a portion of the security was received as collateral for securities lending. At the end of the period, the value of
	these securities totaled $1,098,477 or 2.43% of net assets.
^(f)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Consumer, Non-cyclical		99.35	%
Money Market Funds		2.65	%
Industrial		0.22	%
Technology		0.18	%
Basic Materials		0.06	%
Other Assets and Liabilities		(2.46	)%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		15


		Schedule of Investments
		Principal Healthcare Innovators ETF
		September 30, 2023 (unaudited)

		June 30, 2023	Purchases			Sales		September 30, 2023
Affiliated Securities		Value		Cost		Proceeds		Value
Principal Government Money
Market Fund — Class R-6 5.26%	$	1,429,219	$	4,485,587	$	4,816,329	$	1,098,477
	$	1,429,219	$	4,485,587	$	4,816,329	$	1,098,477

					Realized Gain
				Realized		from		Change in
			Gain/(Loss) on		Capital Gain			Unrealized
		Income ^(a)	Investments		Distributions			Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%	$	—	$	—	$	—	$	—
	$	—	$	—	$	—	$	—

^(a)Amount excludes earnings from securities lending collateral.

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 98.03%	Shares Held		Value

Advertising — 0.48%
Dentsu Group, Inc.	500	$	14,722
Hakuhodo DY Holdings, Inc.	1,000		8,227
Publicis Groupe SA	383		29,058
WPP PLC	2,183		19,523
		$	71,530

Aerospace & Defense — 1.31%
Airbus SE	195		26,178
BAE Systems PLC	4,150		50,523
Dassault Aviation SA	99		18,673
Elbit Systems Ltd.	12		2,385
MTU Aero Engines AG	34		6,174
Rheinmetall AG	59		15,214
Rolls-Royce Holdings PLC ^(a)	10,552		28,440
Safran SA	163		25,615
Singapore Technologies Engineering Ltd.	800		2,288
Thales SA	146		20,545
		$	196,035

Agriculture — 0.88%
British American Tobacco PLC	1,661		52,225
Imperial Brands PLC	1,525		31,017
Japan Tobacco, Inc.	1,500		34,529
Wilmar International Ltd.	5,100		13,916
		$	131,687

Airlines — 0.23%
Air Canada ^(a)	402		5,736
Deutsche Lufthansa AG ^(a)	1,309		10,388
Qantas Airways Ltd. ^(a)	2,831		9,429
Singapore Airlines Ltd.	2,000		9,451
		$	35,004

Apparel — 1.85%
Burberry Group PLC	269		6,264
Gildan Activewear, Inc.	404		11,323
Hermes International SCA	22		40,234
Kering SA	57		26,028
LVMH Moet Hennessy Louis Vuitton SE	244		184,809
Puma SE	121		7,522
		$	276,180

Auto Manufacturers — 3.52%
Bayerische Motoren Werke AG	447		45,548
Daimler Truck Holding AG	540		18,737
Ferrari NV	120		35,486
Honda Motor Co. Ltd.	4,200		47,272
Isuzu Motors Ltd.	1,200		15,100
Mazda Motor Corp.	1,500		17,029
Mercedes-Benz Group AG	570		39,707
Renault SA	365		15,002
Stellantis NV	2,639		50,807
Subaru Corp.	1,200		23,335
Toyota Motor Corp.	9,300		166,627
Volkswagen AG	39		5,142
Volvo AB, Class A	614		12,780
Volvo AB, Class B	1,291		26,658

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Auto Manufacturers (continued)
Volvo Car AB, Class B ^(a)	1,444	$	5,874
		$	525,104

Auto Parts & Equipment — 0.27%
Cie Generale des Etablissements Michelin SCA	361		11,095
Continental AG	92		6,493
NGK Insulators Ltd.	900		11,937
Valeo SE	634		10,946
		$	40,471

Banks — 10.79%
ABN AMRO Bank NV, GDR ^(b)	862		12,249
AIB Group PLC	2,974		13,395
ANZ Group Holdings Ltd.	1,511		24,929
Banco Bilbao Vizcaya Argentaria SA	7,231		58,943
Banco Santander SA	12,017		45,973
Bank Hapoalim BM	1,841		16,357
Bank Leumi Le-Israel BM	2,070		17,100
Bank of Ireland Group PLC	2,503		24,584
Bank of Montreal	572		48,253
Bank of Nova Scotia	581		26,042
Banque Cantonale Vaudoise	136		14,271
Barclays PLC	7,376		14,304
BNP Paribas SA	787		50,281
BOC Hong Kong Holdings Ltd.	3,500		9,587
CaixaBank SA	4,936		19,758
Canadian Imperial Bank of Commerce	467		18,027
Chiba Bank Ltd.	2,100		15,282
Commerzbank AG	1,612		18,389
Commonwealth Bank of Australia	769		49,428
Computershare Ltd.	544		9,080
Concordia Financial Group Ltd.	3,700		16,873
Credit Agricole SA	1,767		21,843
Danske Bank A/S	426		9,925
DBS Group Holdings Ltd.	1,600		39,374
Deutsche Bank AG	1,094		12,087
DNB Bank ASA	720		14,512
Erste Group Bank AG	498		17,280
FinecoBank Banca Fineco SpA	983		11,967
First International Bank Of Israel Ltd.	290		12,438
Hang Seng Bank Ltd.	695		8,649
HSBC Holdings PLC ^(a)	17,549		138,083
ING Groep NV	2,914		38,664
Intesa Sanpaolo SpA	6,555		16,910
Israel Discount Bank Ltd., Class A	2,678		14,456
KBC Group NV	280		17,507
Lloyds Banking Group PLC	53,580		29,006
Macquarie Group Ltd.	191		20,598
Mediobanca Banca di Credito Finanziario SpA	1,496		19,818
Mitsubishi UFJ Financial Group, Inc.	10,600		89,977
Mizrahi Tefahot Bank Ltd.	397		14,374
Mizuho Financial Group, Inc.	3,000		51,010
National Australia Bank Ltd.	1,487		27,793
National Bank of Canada	399		26,506
NatWest Group PLC	2,880		8,282
Nordea Bank Abp	1,352		14,864
Oversea-Chinese Banking Corp. Ltd.	3,300		30,924
Royal Bank of Canada	733		64,058

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Banks (continued)
Skandinaviska Enskilda Banken AB, Class A	1,766	$	21,118
Societe Generale SA	889		21,660
Standard Chartered PLC	2,641		24,425
Sumitomo Mitsui Financial Group, Inc.	1,200		58,996
Svenska Handelsbanken AB, Class A	972		8,679
Swedbank AB, Class A	1,063		19,585
Toronto-Dominion Bank	797		48,017
UBS Group AG ^(a)	2,350		58,253
UniCredit SpA	783		18,816
United Overseas Bank Ltd.	700		14,594
Westpac Banking Corp.	1,720		23,389
		$	1,611,542

Beverages — 2.03%
Anheuser-Busch InBev SA	410		22,762
Asahi Group Holdings Ltd.	600		22,444
Budweiser Brewing Co. APAC Ltd. ^(b)	1,900		3,751
Carlsberg A/S, Class B	73		9,224
Coca-Cola Europacific Partners PLC	479		29,928
Coca-Cola HBC AG ^(a)	558		15,312
Davide Campari-Milano NV	1,258		14,850
Diageo PLC	974		36,055
Endeavour Group Ltd.	2,007		6,800
Heineken Holding NV	202		15,249
Heineken NV	390		34,413
JDE Peet's NV	647		18,072
Kirin Holdings Co. Ltd.	1,400		19,608
Pernod Ricard SA	183		30,540
Remy Cointreau SA	36		4,402
Suntory Beverage & Food Ltd.	400		12,179
Treasury Wine Estates Ltd.	946		7,499
		$	303,088

Biotechnology — 0.60%
Argenx SE ^(a)	12		5,844
Argenx SE ^(a)	24		11,687
Bachem Holding AG, Class B	66		4,903
CSL Ltd.	204		32,895
Genmab A/S ^(a)	74		26,308
Swedish Orphan Biovitrum AB ^(a)	361		7,382
		$	89,019

Building Materials — 1.52%
AGC, Inc.	400		14,036
Cie de Saint-Gobain SA	665		39,991
Daikin Industries Ltd.	200		31,417
Geberit AG	20		10,029
Heidelberg Materials AG	222		17,256
Holcim AG ^(a)	754		48,419
Investment AB Latour, Class B	314		5,540
James Hardie Industries PLC, CDI ^(a)	369		9,677
Kingspan Group PLC	120		9,003
Nibe Industrier AB, Class B	1,735		11,402
Sika AG	59		15,025
West Fraser Timber Co. Ltd.	82		5,953
Xinyi Glass Holdings Ltd.	7,000		9,064
		$	226,812

See accompanying notes.


	Schedule of Investments
	Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Chemicals — 2.52%
Air Liquide SA	220	$	37,178
Arkema SA	145		14,343
BASF SE	690		31,332
Brenntag SE	226		17,557
Chr Hansen Holding A/S	90		5,516
Clariant AG ^(a)	497		7,873
Croda International PLC	104		6,237
EMS-Chemie Holding AG	3		2,042
Evonik Industries AG	311		5,697
Givaudan SA	5		16,354
ICL Group Ltd.	1,923		10,623
Johnson Matthey PLC	505		10,031
Nippon Sanso Holdings Corp.	600		14,233
Nissan Chemical Corp.	400		17,021
Nitto Denko Corp.	300		19,689
Novozymes A/S, Class B	150		6,054
Nutrien Ltd.	435		26,864
OCI NV ^(a)	432		12,053
Shin-Etsu Chemical Co. Ltd.	1,600		46,499
Solvay SA	199		22,060
Sumitomo Chemical Co. Ltd.	3,800		10,349
Symrise AG	27		2,578
Tosoh Corp.	900		11,551
Umicore SA	441		10,467
Yara International ASA	341		12,921
		$	377,122

Coal — 0.08%
Teck Resources Ltd., Class B	271		11,664

Commercial Services — 2.45%
Adecco Group AG	191		7,879
Adyen NV ^(a),(b)	9		6,715
Amadeus IT Group SA	394		23,860
Ashtead Group PLC	395		24,107
Brambles Ltd.	2,124		19,556
Bureau Veritas SA	82		2,038
Edenred SE	357		22,375
Element Fleet Management Corp.	1,096		15,727
Experian PLC	412		13,527
IDP Education Ltd.	353		4,852
Intertek Group PLC	351		17,610
Persol Holdings Co. Ltd.	6,000		9,772
Randstad NV	222		12,294
RB Global, Inc.	147		9,204
Recruit Holdings Co. Ltd.	1,300		40,094
RELX PLC	1,555		52,649
Rentokil Initial PLC	1,437		10,698
Secom Co. Ltd.	400		27,141
Securitas AB, Class B	778		6,171
SGS SA	25		2,104
TOPPAN, Inc.	700		16,746
Transurban Group	1,811		14,776
Worldline SA ^(a),(b)	192		5,410
		$	365,305

Computers — 1.27%
Bechtle AG	139		6,501

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Computers (continued)
Capgemini SE	145	$	25,417
CGI, Inc. ^(a)	371		36,569
Check Point Software Technologies Ltd. ^(a)	90		11,995
Logitech International SA	138		9,540
NEC Corp.	500		27,640
Nomura Research Institute Ltd.	800		20,841
NTT Data Corp.	1,200		16,096
Otsuka Corp.	300		12,712
SCSK Corp.	700		12,221
Teleperformance SE	76		9,594
		$	189,126

Cosmetics & Personal Care — 1.58%
Beiersdorf AG	86		11,106
Essity AB, Class B	420		9,069
Haleon PLC	3,602		14,980
L'Oreal SA	177		73,581
Unilever PLC	2,554		126,577
		$	235,313

Distribution/Wholesale — 1.92%
Bunzl PLC	537		19,171
D'ieteren Group	31		5,241
IMCD NV	50		6,343
ITOCHU Corp.	1,400		50,645
Marubeni Corp.	2,000		31,210
Mitsubishi Corp.	1,100		52,468
Mitsui & Co. Ltd.	1,300		47,175
Sumitomo Corp.	1,700		33,945
Toromont Industries Ltd.	128		10,425
Toyota Tsusho Corp.	500		29,427
		$	286,050

Diversified Financial Services — 1.59%
abrdn PLC	2,329		4,426
AerCap Holdings NV ^(a)	129		8,084
Amundi SA ^(b)	200		11,281
ASX Ltd.	53		1,946
Brookfield Asset Management Ltd., Class A	287		9,564
Deutsche Boerse AG	178		30,807
Euronext NV ^(b)	188		13,118
Futu Holdings Ltd., ADR ^(a)	230		13,296
IGM Financial, Inc.	239		6,062
Julius Baer Group Ltd.	255		16,397
London Stock Exchange Group PLC	50		5,023
Mitsubishi HC Capital, Inc.	2,600		17,329
Nomura Holdings, Inc.	5,800		23,252
ORIX Corp.	1,600		29,904
SBI Holdings, Inc.	700		14,746
Schroders PLC	1,214		6,031
Singapore Exchange Ltd.	1,400		9,985
TMX Group Ltd.	735		15,796
		$	237,047

Electric — 2.60%
BKW AG	134		23,642
Brookfield Renewable Corp., Class A	452		10,819
CLP Holdings Ltd.	528		3,907

See accompanying notes.


Schedule of Investments
Principal International Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Electric (continued)
E.ON SE	2,300	$	27,235
EDP - Energias de Portugal SA	2,218		9,230
Elia Group SA	64		6,269
Emera, Inc.	287		10,020
Endesa SA	1,105		22,518
Enel SpA	4,086		25,142
Engie SA	1,922		29,526
Fortis, Inc.	356		13,522
Hydro One Ltd. ^(b)	614		15,632
Iberdrola SA	4,839		54,204
Mercury NZ Ltd.	1,870		6,837
Meridian Energy Ltd.	2,425		7,471
National Grid PLC	1,826		21,833
Northland Power, Inc.	634		10,325
Origin Energy Ltd.	2,814		15,885
Orsted A/S ^(b)	127		6,933
Power Assets Holdings Ltd.	500		2,420
Redeia Corp. SA	546		8,598
RWE AG	691		25,679
SSE PLC	686		13,476
Terna - Rete Elettrica Nazionale	1,357		10,226
Verbund AG	86		7,006
		$	388,355

Electrical Components & Equipment — 1.06%
ABB Ltd.	1,354		48,518
Legrand SA	291		26,859
Prysmian SpA	603		24,321
Schneider Electric SE	350		58,089
		$	157,787

Electronics — 0.83%
Assa Abloy AB, Class B	499		10,879
Halma PLC	293		6,930
Hirose Electric Co. Ltd.	100		11,590
Hoya Corp.	300		30,765
Ibiden Co. Ltd.	300		15,988
Murata Manufacturing Co. Ltd.	300		5,488
Shimadzu Corp.	445		11,828
TDK Corp.	700		25,960
Venture Corp. Ltd.	573		5,185
		$	124,613

Energy — Alternate Sources — 0.12%
Corp. ACCIONA Energias Renovables SA	335		8,642
Vestas Wind Systems A/S ^(a)	418		8,980
		$	17,622

Engineering & Construction — 1.74%
Acciona SA	45		5,742
ACS Actividades de Construccion y Servicios SA	542		19,523
Aena SME SA ^(b)	52		7,840
Auckland International Airport Ltd.	1,593		7,552
Bouygues SA	481		16,853
Cellnex Telecom SA ^(a),(b)	279		9,725
CK Infrastructure Holdings Ltd.	500		2,366
Eiffage SA	238		22,656
Ferrovial SE	399		12,221

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Engineering & Construction (continued)
Infrastrutture Wireless Italiane SpA ^(b)	964	$	11,481
Kajima Corp.	1,400		22,798
Keppel Corp. Ltd.	3,900		19,400
Skanska AB, Class B	411		6,771
Vinci SA	631		70,062
WSP Global, Inc.	172		24,276
		$	259,266

Entertainment — 0.88%
Aristocrat Leisure Ltd.	476		12,502
Evolution AB ^(b)	173		17,519
Flutter Entertainment PLC ^(a)	149		24,402
Genting Singapore Ltd.	10,000		6,182
La Francaise des Jeux SAEM ^(b)	359		11,690
Lottery Corp. Ltd.	2,538		7,702
Oriental Land Co. Ltd.	900		29,564
Universal Music Group NV	830		21,701
		$	131,262

Environmental Control — 0.06%
GFL Environmental, Inc.	281		8,923

Food — 4.44%
Barry Callebaut AG	5		7,964
Carrefour SA	436		7,507
Chocoladefabriken Lindt & Spruengli AG	1		11,132
CK Hutchison Holdings Ltd.	2,000		10,701
Coles Group Ltd.	1,045		10,454
Danone SA	332		18,344
Empire Co. Ltd., Class A	616		16,758
George Weston Ltd.	204		22,624
J Sainsbury PLC	6,816		21,023
Jeronimo Martins SGPS SA	736		16,543
Kerry Group PLC, Class A	31		2,595
Kesko Oyj, Class B	752		13,492
Koninklijke Ahold Delhaize NV	1,418		42,757
Loblaw Cos. Ltd.	253		21,495
Metro, Inc.	395		20,514
Mowi ASA	841		14,903
Nestle SA	2,424		274,721
Orkla ASA	2,151		16,083
Salmar ASA	146		7,417
Saputo, Inc.	325		6,796
Seven & i Holdings Co. Ltd.	900		35,262
Tesco PLC	4,829		15,566
WH Group Ltd. ^(b)	36,500		19,157
Woolworths Group Ltd.	1,233		29,586
		$	663,394

Food Service — 0.43%
Compass Group PLC	1,537		37,506
Sodexo SA ^(a)	255		26,291
		$	63,797

Forest Products & Paper — 0.48%
Holmen AB, Class B	311		12,121
Mondi PLC	1,053		17,633
Oji Holdings Corp.	3,500		14,732

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Forest Products & Paper (continued)
Smurfit Kappa Group PLC	434	$	14,481
UPM-Kymmene Oyj	366		12,564
		$	71,531

Gas — 0.55%
AltaGas Ltd.	903		17,319
Canadian Utilities Ltd., Class A	512		10,819
Enagas SA	456		7,559
Hong Kong & China Gas Co. Ltd.	3,250		2,266
Naturgy Energy Group SA	503		13,699
Snam SpA	2,060		9,690
Tokyo Gas Co. Ltd.	900		20,422
		$	81,774

Hand/Machine Tools — 0.26%
Fuji Electric Co. Ltd.	400		18,057
Schindler Holding AG	31		6,198
Schindler Holding AG	28		5,408
Techtronic Industries Co. Ltd.	1,000		9,705
		$	39,368

Healthcare — Products — 1.08%
Alcon, Inc.	68		5,270
Carl Zeiss Meditec AG	48		4,203
Cochlear Ltd.	115		18,878
Coloplast A/S, Class B	96		10,174
Demant A/S ^(a)	175		7,259
DiaSorin SpA	54		4,934
EBOS Group Ltd.	487		9,982
EssilorLuxottica SA	146		25,494
Fisher & Paykel Healthcare Corp. Ltd., Class C	448		5,794
Lifco AB, Class B	343		6,026
Olympus Corp.	1,600		20,787
QIAGEN NV ^(a)	230		9,306
Sartorius Stedim Biotech	23		5,496
Siemens Healthineers AG ^(b)	174		8,830
Smith & Nephew PLC	197		2,459
Sonova Holding AG	34		8,086
Straumann Holding AG	69		8,835
		$	161,813

Healthcare — Services — 0.55%
BioMerieux	129		12,523
Eurofins Scientific SE	118		6,674
Fresenius Medical Care AG & Co. KGaA	192		8,290
Fresenius SE & Co. KGaA	318		9,905
Lonza Group AG	29		13,484
Medibank Pvt Ltd.	7,106		15,717
Ramsay Health Care Ltd.	53		1,767
Sonic Healthcare Ltd.	713		13,661
		$	82,021

Holding Companies — Diversified — 0.21%
Jardine Matheson Holdings Ltd.	383		17,779
Swire Pacific Ltd., Class A	2,000		13,498
		$	31,277

See accompanying notes.


Schedule of Investments
Principal International Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Home Builders — 0.69%
Barratt Developments PLC	1,216	$	6,544
Berkeley Group Holdings PLC	118		5,913
Daiwa House Industry Co. Ltd.	900		24,180
Iida Group Holdings Co. Ltd.	700		11,647
Open House Group Co. Ltd.	300		10,186
Persimmon PLC	436		5,732
Sekisui Chemical Co. Ltd.	900		12,967
Sekisui House Ltd.	1,000		19,921
Taylor Wimpey PLC	4,706		6,735
		$	103,825

Home Furnishings — 0.67%
Rational AG	8		5,075
SEB SA	56		5,249
Sony Group Corp.	1,100		90,096
		$	100,420

Household Products/Wares — 0.34%
Henkel AG & Co. KGaA	127		8,019
Reckitt Benckiser Group PLC	598		42,274
		$	50,293

Insurance — 4.85%
Aegon NV	1,743		8,444
Ageas SA	220		9,078
AIA Group Ltd.	10,400		84,797
Allianz SE	305		72,780
Assicurazioni Generali SpA	1,269		25,981
AXA SA	1,568		46,716
Baloise Holding AG	62		9,002
Fairfax Financial Holdings Ltd.	32		26,122
Gjensidige Forsikring ASA	92		1,355
Great-West Lifeco, Inc.	892		25,520
Hannover Rueck SE	141		30,992
iA Financial Corp., Inc.	249		15,619
Insurance Australia Group Ltd.	2,886		10,540
Intact Financial Corp.	270		39,363
Japan Post Holdings Co. Ltd.	3,100		24,841
Manulife Financial Corp.	2,578		47,109
Muenchener Rueckversicherungs-Gesellschaft AG in Muenchen	69		26,926
NN Group NV	288		9,269
Phoenix Group Holdings PLC	298		1,753
Power Corp. of Canada	486		12,373
Prudential PLC	1,166		12,644
QBE Insurance Group Ltd.	1,862		18,808
Sampo Oyj, Class A	787		34,098
Sun Life Financial, Inc.	361		17,613
Suncorp Group Ltd.	2,256		20,263
Swiss Life Holding AG	23		14,363
Swiss Re AG	306		31,531
Tokio Marine Holdings, Inc.	1,600		37,098
Tryg A/S	106		1,944
Zurich Insurance Group AG	17		7,802
		$	724,744

Internet — 1.06%
Adevinta ASA ^(a)	781		7,732
Auto Trader Group PLC ^(b)	1,276		9,615

See accompanying notes.


Schedule of Investments
Principal International Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Internet (continued)
Delivery Hero SE ^(a),(b)	183	$	5,257
Prosus NV ^(a)	1,235		36,455
Scout24 SE ^(b)	105		7,289
SEEK Ltd.	406		5,761
Shopify, Inc., Class A ^(a)	1,040		56,768
United Internet AG	609		13,045
Wix.com Ltd. ^(a)	61		5,600
ZOZO, Inc.	600		11,011
		$	158,533

Investment Companies — 0.33%
EXOR NV	30		2,662
Groupe Bruxelles Lambert NV	29		2,164
Industrivarden AB, Class A	209		5,525
Industrivarden AB, Class C	215		5,679
Washington H Soul Pattinson & Co. Ltd.	1,109		23,238
Wendel SE	125		9,918
		$	49,186

Iron & Steel — 0.83%
ArcelorMittal SA	327		8,220
BlueScope Steel Ltd.	530		6,624
Fortescue Metals Group Ltd.	2,495		33,559
JFE Holdings, Inc.	1,400		20,526
Mineral Resources Ltd.	279		12,132
Nippon Steel Corp.	1,200		28,145
voestalpine AG	561		15,326
		$	124,532

Leisure Time — 0.35%
BRP, Inc.	233		17,636
Shimano, Inc.	100		13,494
Yamaha Motor Co. Ltd.	800		21,044
		$	52,174

Lodging — 0.40%
Accor SA	215		7,260
City Developments Ltd.	2,300		11,121
Galaxy Entertainment Group Ltd.	1,000		6,021
InterContinental Hotels Group PLC	161		11,932
Sands China Ltd. ^(a)	2,000		6,130
Whitbread PLC	418		17,666
		$	60,130

Machinery — Construction & Mining — 1.22%
Epiroc AB, Class A	465		8,853
Epiroc AB, Class B	428		6,863
Hitachi Construction Machinery Co. Ltd.	600		18,252
Hitachi Ltd.	900		55,858
Komatsu Ltd.	1,300		35,171
Metso Oyj	1,448		15,239
Mitsubishi Heavy Industries Ltd.	500		27,924
Sandvik AB	502		9,263
Siemens Energy AG ^(a)	377		4,934
		$	182,357

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Machinery — Diversified — 1.11%
Atlas Copco AB, Class A	1,170	$	15,769
Atlas Copco AB, Class B	1,738		20,393
CNH Industrial NV	1,305		15,922
FANUC Corp.	200		5,210
GEA Group AG	358		13,232
Keyence Corp.	200		74,277
Kone Oyj, Class B	175		7,386
Spirax-Sarco Engineering PLC	57		6,625
Wartsila Oyj Abp	636		7,232
		$	166,046

Media — 0.71%
Bollore SE	2,414		12,991
Informa PLC	1,276		11,683
Pearson PLC	1,508		15,978
Quebecor, Inc., Class B	895		19,182
Thomson Reuters Corp.	106		12,967
Vivendi SE	222		1,947
Wolters Kluwer NV	255		30,909
		$	105,657

Metal Fabrication & Hardware — 0.25%
SKF AB, Class B	366		6,102
Tenaris SA	1,452		23,004
VAT Group AG ^(b)	23		8,267
		$	37,373

Mining — 2.48%
Anglo American PLC	506		13,987
Antofagasta PLC	387		6,747
BHP Group Ltd.	4,451		126,633
Boliden AB ^(a)	426		12,261
First Quantum Minerals Ltd.	445		10,514
Franco-Nevada Corp.	117		15,620
Glencore PLC	7,413		42,501
IGO Ltd.	803		6,536
Lundin Mining Corp.	1,089		8,122
Norsk Hydro ASA	2,259		14,192
Northern Star Resources Ltd.	931		6,261
Pilbara Minerals Ltd.	8,277		22,883
Rio Tinto Ltd.	329		24,019
Rio Tinto PLC	380		23,989
South32 Ltd.	6,286		13,701
Sumitomo Metal Mining Co. Ltd.	500		14,718
Wheaton Precious Metals Corp.	205		8,319
		$	371,003

Miscellaneous Manufacturers — 0.57%
Alfa Laval AB	210		7,223
Alstom SA	256		6,117
Indutrade AB	337		6,252
Knorr-Bremse AG	95		6,045
Orica Ltd.	848		8,500
Siemens AG	298		42,741
Smiths Group PLC	428		8,457
		$	85,335

See accompanying notes.


Schedule of Investments
Principal International Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Office & Business Equipment — 0.21%
Ricoh Co. Ltd.	1,700	$	14,681
Seiko Epson Corp.	1,100		17,294
		$	31,975

Oil & Gas — 6.46%
Aker BP ASA	623		17,240
Ampol Ltd.	1,042		22,644
ARC Resources Ltd.	1,317		21,022
BP PLC	15,906		103,128
Canadian Natural Resources Ltd.	807		52,190
Cenovus Energy, Inc.	1,399		29,128
DCC PLC	162		9,110
Eni SpA	3,104		50,066
Equinor ASA	899		29,512
Galp Energia SGPS SA	1,182		17,545
Idemitsu Kosan Co. Ltd.	600		13,804
Imperial Oil Ltd.	343		21,127
Inpex Corp.	1,700		25,664
Neste Oyj	213		7,235
OMV AG	462		22,136
Parkland Corp.	575		16,819
Repsol SA	2,129		35,046
Santos Ltd.	3,992		20,277
Shell PLC	6,211		197,484
Suncor Energy, Inc.	1,056		36,316
TotalEnergies SE	2,186		144,008
Tourmaline Oil Corp.	420		21,135
Woodside Energy Group Ltd.	2,215		51,967
		$	964,603

Oil & Gas Services — 0.05%
Seatrium Ltd. ^(a)	71,127		6,972

Packaging & Containers — 0.19%
CCL Industries, Inc., Class B	508		21,322
Stora Enso Oyj, Class R	550		6,914
		$	28,236

Pharmaceuticals — 7.83%
Amplifon SpA	205		6,095
Astellas Pharma, Inc.	100		1,388
AstraZeneca PLC	1,363		184,626
Bayer AG	698		33,540
Chugai Pharmaceutical Co. Ltd.	1,000		30,942
Daiichi Sankyo Co. Ltd.	1,500		41,214
GSK PLC	3,224		58,689
Hikma Pharmaceuticals PLC	395		10,063
Ipsen SA	162		21,272
Merck KGaA	62		10,367
Nippon Shinyaku Co. Ltd.	300		12,706
Novartis AG	976		100,090
Novo Nordisk A/S, Class B	2,916		266,160
Ono Pharmaceutical Co. Ltd.	800		15,353
Orion Oyj, Class B	317		12,474
Recordati Industria Chimica e Farmaceutica SpA	200		9,454
Roche Holding AG	619		169,365
Roche Holding AG	33		9,712
Sanofi	866		92,913

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Pharmaceuticals (continued)
Shionogi & Co. Ltd.	500	$	22,370
Takeda Pharmaceutical Co. Ltd.	1,300		40,373
Teva Pharmaceutical Industries Ltd., ADR ^(a)	1,765		18,003
UCB SA	30		2,459
		$	1,169,628

Pipelines — 0.31%
APA Group	1,454		7,759
Enbridge, Inc.	245		8,126
Keyera Corp.	99		2,325
Pembina Pipeline Corp.	765		23,002
TC Energy Corp.	131		4,505
		$	45,717

Private Equity — 0.50%
3i Group PLC	1,019		25,773
Brookfield Corp.	553		17,291
CapitaLand Investment Ltd.	5,800		13,153
EQT AB	368		7,306
Eurazeo SE	181		10,802
		$	74,325

Real Estate — 1.24%
Aroundtown SA ^(a)	3,471		7,237
CK Asset Holdings Ltd.	2,000		10,535
Fastighets AB Balder, Class B ^(a)	3,090		13,943
FirstService Corp.	111		16,145
Hang Lung Properties Ltd.	3,000		4,107
Henderson Land Development Co. Ltd.	1,000		2,637
Hongkong Land Holdings Ltd.	516		1,842
Hulic Co. Ltd.	1,600		14,358
LEG Immobilien SE ^(a)	114		7,875
Mitsui Fudosan Co. Ltd.	1,400		30,859
Nomura Real Estate Holdings, Inc.	600		15,068
REA Group Ltd.	74		7,342
Sagax AB, Class B	299		5,706
Sino Land Co. Ltd.	6,000		6,766
Sun Hung Kai Properties Ltd.	1,000		10,701
Swire Properties Ltd.	5,200		10,850
Swiss Prime Site AG	26		2,385
UOL Group Ltd.	2,800		13,150
Wharf Real Estate Investment Co. Ltd.	1,000		3,863
		$	185,369

REITs — 1.07%
British Land Co. PLC	2,793		10,799
Canadian Apartment Properties	70		2,323
CapitaLand Ascendas	7,600		15,289
CapitaLand Integrated Commercial Trust	6,517		8,820
Dexus	1,711		8,031
Gecina SA	57		5,830
Goodman Group	879		12,122
GPT Group	728		1,825
Klepierre SA ^(a)	857		21,048
Land Securities Group PLC	932		6,707
Link	1,540		7,552
Mapletree Logistics Trust	6,200		7,620
Mapletree Pan Asia Commercial Trust	6,100		6,381

See accompanying notes.


	Schedule of Investments
Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

REITs (continued)
Mirvac Group	6,229	$	8,530
RioCan Real Estate Investment Trust	144		1,916
Scentre Group	1,313		2,077
Stockland	6,329		15,951
Vicinity Ltd.	6,239		6,799
Warehouses De Pauw CVA	441		10,929
		$	160,549

Retail — 3.01%
Alimentation Couche-Tard, Inc.	756		38,394
Associated British Foods PLC	695		17,536
Canadian Tire Corp. Ltd., Class A	129		13,871
Cie Financiere Richemont SA, Class A	170		20,801
Dollarama, Inc.	361		24,872
Fast Retailing Co. Ltd.	200		43,616
H & M Hennes & Mauritz AB, Class B	650		9,249
Industria de Diseno Textil SA	880		32,833
Jardine Cycle & Carriage Ltd.	900		21,022
JD Sports Fashion PLC	9,607		17,547
Kingfisher PLC	4,070		11,089
MatsukiyoCocokara & Co.	900		16,143
Moncler SpA	257		14,966
Next PLC	286		25,459
Pan Pacific International Holdings Corp.	900		18,898
Pandora A/S	240		24,890
Reece Ltd.	555		6,648
Restaurant Brands International, Inc.	379		25,239
Swatch Group AG	193		9,456
Swatch Group AG	46		11,830
USS Co. Ltd.	800		13,236
Welcia Holdings Co. Ltd.	600		10,373
Wesfarmers Ltd.	617		20,970
		$	448,938

Semiconductors — 3.23%
Advantest Corp.	1,200		33,574
ASM International NV	55		23,114
ASML Holding NV	355		209,844
Disco Corp.	200		36,911
Hamamatsu Photonics KK	300		12,645
Infineon Technologies AG	948		31,426
Renesas Electronics Corp. ^(a)	1,700		26,000
Rohm Co. Ltd.	800		15,080
STMicroelectronics NV	553		23,962
SUMCO Corp.	1,100		14,346
Tokyo Electron Ltd.	400		54,711
Tower Semiconductor Ltd. ^(a)	48		1,173
		$	482,786

Shipbuilding — 0.08%
Kongsberg Gruppen ASA	302		12,456

Software — 1.44%
Constellation Software, Inc.	19		39,225
Constellation Software, Inc. – Warrants ^(c)	19		—
Dassault Systemes SE	299		11,157
Descartes Systems Group, Inc. ^(a)	200		14,679
Nemetschek SE	100		6,119

See accompanying notes.


Schedule of Investments
Principal International Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Software (continued)
Open Text Corp.	267	$	9,371
Oracle Corp. Japan	200		14,856
Sage Group PLC	1,051		12,682
SAP SE	541		70,250
Square Enix Holdings Co. Ltd.	300		10,289
TIS, Inc.	600		13,221
WiseTech Global Ltd.	316		13,216
		$	215,065

Telecommunications — 3.56%
BCE, Inc.	197		7,520
Bezeq The Israeli Telecommunication Corp. Ltd.	9,694		13,648
BT Group PLC	4,903		6,981
Deutsche Telekom AG	3,588		75,368
Elisa Oyj	277		12,854
Hikari Tsushin, Inc.	100		15,240
HKT Trust & HKT Ltd.	7,000		7,312
KDDI Corp.	1,400		42,879
Koninklijke KPN NV	5,323		17,553
Nice Ltd. ^(a)	79		13,361
Nippon Telegraph & Telephone Corp.	35,000		41,361
Nokia Oyj	5,134		19,367
Orange SA	3,163		36,317
Rogers Communications, Inc., Class B	53		2,035
Singapore Telecommunications Ltd.	1,600		2,832
SoftBank Corp.	3,500		39,593
SoftBank Group Corp.	1,100		46,631
Spark New Zealand Ltd.	7,430		21,420
Swisscom AG	20		11,891
Tele2 AB, Class B	911		6,977
Telecom Italia SpA ^(a)	18,290		5,726
Telefonaktiebolaget LM Ericsson, Class B	1,725		8,420
Telefonica Deutschland Holding AG	4,435		7,948
Telefonica SA	6,054		24,757
Telenor ASA	832		9,450
Telia Co. AB	857		1,770
Telstra Group Ltd.	6,516		16,129
TELUS Corp.	131		2,139
Vodafone Group PLC	15,477		14,506
		$	531,985

Toys, Games & Hobbies — 0.42%
Bandai Namco Holdings, Inc.	1,000		20,356
Nintendo Co. Ltd.	1,000		41,689
		$	62,045

Transportation — 2.23%
AP Moller - Maersk A/S, Class A	6		10,657
AP Moller - Maersk A/S, Class B	7		12,637
Aurizon Holdings Ltd.	3,688		8,276
Canadian National Railway Co.	270		29,239
Canadian Pacific Kansas City Ltd.	94		6,987
Deutsche Post AG	763		31,086
DSV A/S	228		42,630
Getlink SE	587		9,377
Kintetsu Group Holdings Co. Ltd.	500		14,180
Kuehne & Nagel International AG	68		19,389
Mitsui OSK Lines Ltd.	800		22,002

See accompanying notes.


			Schedule of Investments
	Principal International Adaptive Multi-Factor ETF
			September 30, 2023 (unaudited)

COMMON STOCKS (continued)			Shares Held		Value
Transportation (continued)
MTR Corp. Ltd.			500	$	1,979
NIPPON EXPRESS HOLDINGS, Inc.			300		15,665
Nippon Yusen KK			900		23,403
Poste Italiane SpA ^(b)			2,093		22,058
SG Holdings Co. Ltd.			1,100		14,096
SITC International Holdings Co. Ltd.			6,000		10,083
TFI International, Inc.			200		25,686
Yamato Holdings Co. Ltd.			800		13,035
			$		332,465

Water — 0.16%
Severn Trent PLC			70		2,020
United Utilities Group PLC			183		2,117
Veolia Environnement SA			690		20,010
			$		24,147
TOTAL COMMON STOCKS			$		14,639,771
PREFERRED STOCKS — 0.40%			Shares Held		Value
Auto Manufacturers — 0.25%
Bayerische Motoren Werke AG
	9.70%		224	$	20,911
Porsche Automobil Holding SE
	5.50%		128		6,313
Volkswagen AG
	25.58%^(d)		89		10,251
			$		37,475

Electronics — 0.08%
Sartorius AG
	0.45%		35		11,908
Household Products/Wares — 0.07%
Henkel AG & Co. KGaA
	2.75	%	148		10,556
TOTAL PREFERRED STOCKS			$		59,939
INVESTMENT COMPANIES — 0.89%			Shares Held		Value
Money Market Fund — 0.89%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30		% ^(d)	132,644	$	132,644
TOTAL INVESTMENT COMPANIES			$		132,644
Total Investments			$		14,832,354
Other Assets and Liabilities — 0.68%					101,566
Total Net Assets — 100.00%			$		14,933,920

^(a)	Non-income producing security.
^(b)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in
	transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these
	securities totaled $213,817 or 1.43% of net assets.
^(c)	The value of these investments was determined using significant unobservable inputs, in good faith by the Advisor, under
	procedures established and periodically reviewed by the Board of Trustees.
^(d)	1-day yield shown as of period end.




See accompanying notes.			32


	Schedule of Investments
	Principal International Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

	Portfolio Summary
Location	Percent
Japan	20.78	%
United Kingdom	12.08	%
France	10.53	%
Canada	9.79	%
Switzerland	7.59	%
Germany	6.45	%
Australia	6.42	%
Netherlands	4.35	%
Denmark	3.01	%
Spain	2.75	%
Sweden	2.31	%
Italy	2.26	%
Hong Kong	2.06	%
Singapore	1.73	%
Finland	1.10	%
Norway	1.06	%
Israel	1.01	%
United States	0.96	%
Ireland	0.86	%
Belgium	0.73	%
Austria	0.41	%
New Zealand	0.33	%
Luxembourg	0.30	%
Portugal	0.29	%
Jordan	0.07	%
Chile	0.05	%
Mongolia	0.04	%
Other Assets and Liabilities	0.68	%
TOTAL NET ASSETS	100.00	%

See accompanying notes.


Schedule of Investments
Principal Investment Grade Corporate Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS — 89.26%		Amount		Value

Aerospace & Defense — 3.41%
Boeing Co.
3.25%, 02/01/2028	$	600,000	$	541,070
5.71%, 05/01/2040		523,000		482,521
Lockheed Martin Corp.
5.70%, 11/15/2054		260,000		259,350
RTX Corp.
4.13%, 11/16/2028		998,000		930,591
			$	2,213,532

Airlines — 3.12%
Delta Air Lines, Inc./SkyMiles IP Ltd.
4.75%, 10/20/2028 ^(a)		927,262		881,217
United Airlines 2016-2 Class A Pass-Through Trust
3.10%, 04/07/2030		1,327,024		1,139,532
			$	2,020,749

Auto Manufacturers — 0.50%
Mercedes-Benz Finance North America LLC
4.80%, 03/30/2028 ^(a)		335,000		324,526

Banks — 16.55%
Bank of America Corp.
(6-month Secured Overnight Financing Rate + 1.06%),
2.09%, 06/14/2029 ^(b)		1,189,000		995,353
(5-year Treasury Constant Maturity Rate + 1.20%),
2.48%, 09/21/2036 ^(b)		1,056,000		768,428
(6-month Secured Overnight Financing Rate + 1.88%),
2.83%, 10/24/2051 ^(b)		586,000		344,445
(6-month Secured Overnight Financing Rate + 1.99%),
6.20%, 11/10/2028 ^(b)		598,000		600,701
Bank of New York Mellon Corp.
(6-month Secured Overnight Financing Rate + 1.61%),
4.97%, 04/26/2034 ^(b)		516,000		475,798
Canadian Imperial Bank of Commerce
6.09%, 10/03/2033		508,000		504,629
Citigroup, Inc.
(6-month Secured Overnight Financing Rate + 1.55%),
5.61%, 09/29/2026 ^(b)		1,121,000		1,109,602
JPMorgan Chase & Co.
(3-month Term Secured Overnight Financing Rate + 0.70%),
1.04%, 02/04/2027 ^(b)		1,447,000		1,287,763
Morgan Stanley
(6-month Secured Overnight Financing Rate + 1.43%),
2.80%, 01/25/2052 ^(b)		923,000		537,344
3.59%, 07/22/2028		524,000		478,087
5.00%, 11/24/2025		458,000		448,902
State Street Corp.
(6-month Secured Overnight Financing Rate + 1.57%),
4.82%, 01/26/2034 ^(b)		137,000		124,916
(6-month Secured Overnight Financing Rate + 1.89%),
5.16%, 05/18/2034 ^(b)		320,000		297,605
Truist Financial Corp.
(6-month Secured Overnight Financing Rate + 1.63%),
5.90%, 10/28/2026 ^(b)		310,000		306,579
UBS Group AG
(1-year Treasury Constant Maturity Rate + 1.75%),
4.75%, 05/12/2028 ^(a),(b)		1,126,000		1,063,906

See accompanying notes.


Schedule of Investments
Principal Investment Grade Corporate Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Banks (continued)
Wells Fargo & Co.
(6-month Secured Overnight Financing Rate + 2.10%),
2.39%, 06/02/2028 ^(b)	$	1,578,000	$	1,383,857
			$	10,727,915

Beverages — 3.83%
Anheuser-Busch InBev Worldwide, Inc.
3.50%, 06/01/2030		726,000		645,927
4.38%, 04/15/2038		789,000		684,006
Constellation Brands, Inc.
4.75%, 05/09/2032		578,000		535,443
PepsiCo, Inc.
3.90%, 07/18/2032		175,000		159,461
4.20%, 07/18/2052		350,000		289,168
4.45%, 02/15/2033 ^(c)		180,000		172,475
			$	2,486,480

Biotechnology — 0.87%
Amgen, Inc.
5.25%, 03/02/2030		246,000		240,339
5.60%, 03/02/2043		348,000		323,529
			$	563,868

Commercial Services — 1.14%
CoStar Group, Inc.
2.80%, 07/15/2030 ^(a)		917,000		738,867

Computers — 0.73%
Apple, Inc.
3.95%, 08/08/2052		603,000		472,894

Diversified Financial Services — 1.04%
AerCap Ireland Capital DAC/AerCap Global Aviation Trust
3.00%, 10/29/2028		459,000		393,583
3.85%, 10/29/2041		790		560
Blackstone Holdings Finance Co. LLC
2.85%, 08/05/2051 ^(a)		514,342		282,621
			$	676,764

Electric — 11.42%
Commonwealth Edison Co.
4.00%, 03/01/2049		661,000		495,773
Duke Energy Carolinas LLC
3.75%, 06/01/2045		516,000		370,564
Entergy Louisiana LLC
4.95%, 01/15/2045		516,000		431,191
FirstEnergy Corp.
5.10%, 07/15/2047		388,000		329,279
Florida Power & Light Co.
3.95%, 03/01/2048		388,000		296,013
ITC Holdings Corp.
3.65%, 06/15/2024		548,000		538,695
Kentucky Utilities Co.
4.38%, 10/01/2045		335,000		259,327
Louisville Gas & Electric Co.
5.45%, 04/15/2033		190,000		186,078

See accompanying notes.


	Schedule of Investments
	Principal Investment Grade Corporate Active ETF
	September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Electric (continued)
MidAmerican Energy Co.
4.40%, 10/15/2044	$	516,000	$	417,252
Monongahela Power Co.
3.55%, 05/15/2027 ^(a)		404,000		373,604
Northern States Power Co.
5.10%, 05/15/2053		283,000		253,206
NRG Energy, Inc.
2.00%, 12/02/2025 ^(a)		522,000		472,376
Pacific Gas & Electric Co.
1.70%, 11/15/2023		794,000		789,568
2.95%, 03/01/2026		994,000		915,509
WEC Energy Group, Inc.
1.38%, 10/15/2027		1,051,000		890,530
5.00%, 09/27/2025		391,000		385,269
			$	7,404,234

Environmental Control — 1.57%
Waste Connections, Inc.
4.20%, 01/15/2033		727,000		649,318
Waste Management, Inc.
4.63%, 02/15/2030		388,000		370,578
			$	1,019,896

Food — 2.47%
JBS USA LUX SA/JBS USA Food Co./JBS USA Finance, Inc.
4.38%, 02/02/2052		442,200		293,876
Kraft Heinz Foods Co.
4.88%, 10/01/2049		529,000		441,576
Mars, Inc.
2.38%, 07/16/2040 ^(a)		461,000		291,572
Pilgrim's Pride Corp.
3.50%, 03/01/2032		742,000		573,790
Sysco Corp.
3.15%, 12/14/2051		736		453
			$	1,601,267

Gas — 1.89%
NiSource, Inc.
0.95%, 08/15/2025		1,263,000		1,151,862
5.25%, 03/30/2028		72,000		70,563
			$	1,222,425

Healthcare — Products — 1.85%
Abbott Laboratories
4.90%, 11/30/2046		350,000		318,637
Boston Scientific Corp.
2.65%, 06/01/2030		1,055,000		881,800
			$	1,200,437

Healthcare — Services — 2.33%
Centene Corp.
2.45%, 07/15/2028		1,131,000		955,519
UnitedHealth Group, Inc.
2.75%, 05/15/2040		532,000		361,458

See accompanying notes.


	Schedule of Investments
	Principal Investment Grade Corporate Active ETF
	September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Healthcare — Services (continued)
UnitedHealth Group, Inc. (continued)
5.88%, 02/15/2053	$	194,000	$	194,690
			$	1,511,667

Insurance — 4.05%
Arthur J Gallagher & Co.
2.40%, 11/09/2031 ^(c)		649,000		497,999
5.50%, 03/02/2033		266,000		254,789
Chubb INA Holdings, Inc.
3.35%, 05/03/2026		531,000		503,656
Corebridge Financial, Inc.
4.40%, 04/05/2052		344,000		251,662
Everest Reinsurance Holdings, Inc.
3.13%, 10/15/2052		467,000		276,745
Markel Group, Inc.
4.30%, 11/01/2047		464,000		340,935
MetLife, Inc.
5.00%, 07/15/2052		257,000		221,750
New York Life Insurance Co.
3.75%, 05/15/2050 ^(a)		404,000		278,870
			$	2,626,406

Internet — 1.93%
Amazon.com, Inc.
4.55%, 12/01/2027		1,114,000		1,090,950
Netflix, Inc.
4.88%, 04/15/2028		85,000		82,358
5.88%, 11/15/2028		75,000		75,424
			$	1,248,732

Media — 1.85%
Charter Communications Operating LLC/Charter Communications Operating
Capital
2.30%, 02/01/2032		665,000		484,635
Comcast Corp.
3.97%, 11/01/2047		598,000		446,159
4.80%, 05/15/2033		283,000		265,494
			$	1,196,288

Mining — 0.78%
Glencore Funding LLC
6.13%, 10/06/2028		508,000		507,128

Pharmaceuticals — 8.82%
AbbVie, Inc.
3.20%, 11/21/2029		534,000		471,227
4.05%, 11/21/2039		790,000		646,317
Astrazeneca Finance LLC
4.88%, 03/03/2033		187,000		180,426
Bayer U.S. Finance II LLC
4.63%, 06/25/2038 ^(a)		864,000		709,201
Becton Dickinson & Co.
3.70%, 06/06/2027		1,384,000		1,297,000
Bristol-Myers Squibb Co.
4.13%, 06/15/2039		388,000		323,569
CVS Health Corp.
5.13%, 02/21/2030		340,000		327,020

See accompanying notes.


	Schedule of Investments
Principal Investment Grade Corporate Active ETF
	September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Pharmaceuticals (continued)
CVS Health Corp. (continued)
5.30%, 06/01/2033	$	350,000	$	331,507
Eli Lilly & Co.
4.70%, 02/27/2033		266,000		256,069
Pfizer Investment Enterprises Pte. Ltd.
5.11%, 05/19/2043		271,000		248,872
Zoetis, Inc.
3.90%, 08/20/2028		984,000		924,546
			$	5,715,754

Pipelines — 4.40%
Energy Transfer LP
3.75%, 05/15/2030		669,000		582,761
5.15%, 03/15/2045		455,000		366,601
Enterprise Products Operating LLC
3.13%, 07/31/2029		1,070,000		940,036
MPLX LP
4.88%, 12/01/2024		523,000		515,587
Sabine Pass Liquefaction LLC
5.00%, 03/15/2027		460,000		446,254
			$	2,851,239

REITs — 2.09%
Invitation Homes Operating Partnership LP
2.00%, 08/15/2031		392,000		290,096
Kimco Realty OP LLC
3.20%, 04/01/2032		732,000		589,180
Realty Income Corp.
3.10%, 12/15/2029		70		60
Spirit Realty LP
3.20%, 02/15/2031		588,000		474,976
			$	1,354,312

Retail — 0.27%
Walmart, Inc.
4.50%, 04/15/2053		206,000		177,313

Semiconductors — 1.49%
Broadcom, Inc.
3.63%, 10/15/2024		548,000		534,564
4.11%, 09/15/2028		469,000		432,642
			$	967,206

Software — 5.41%
Fiserv, Inc.
4.40%, 07/01/2049		462,000		353,910
Intuit, Inc.
5.50%, 09/15/2053		220,000		211,074
Microsoft Corp.
2.53%, 06/01/2050		720,000		438,404
Oracle Corp.
2.80%, 04/01/2027		388,000		352,292
4.00%, 07/15/2046		388,000		273,789
6.15%, 11/09/2029		201,000		204,046
Take-Two Interactive Software, Inc.
4.00%, 04/14/2032		600,000		523,334

See accompanying notes.


		Schedule of Investments
	Principal Investment Grade Corporate Active ETF
		September 30, 2023 (unaudited)

			Principal
BONDS (continued)			Amount		Value
Software (continued)
VMware, Inc.
	4.65%, 05/15/2027	$	1,191,000	$	1,148,567
				$	3,505,416

Telecommunications — 3.19%
AT&T, Inc.
	3.50%, 09/15/2053		1,262,000		779,725
T-Mobile USA, Inc.
	3.38%, 04/15/2029		1,267,000		1,114,377
	6.00%, 06/15/2054		183,000		174,440
				$	2,068,542

Transportation — 0.46%
Norfolk Southern Corp.
	5.35%, 08/01/2054		330,000		301,472
Trucking & Leasing — 0.94%
Penske Truck Leasing Co. LP/PTL Finance Corp.
	3.45%, 07/01/2024 ^(a)		548,000		537,497
	6.20%, 06/15/2030 ^(a)		74,000		72,924
				$	610,421

Water — 0.86%
Essential Utilities, Inc.
	2.40%, 05/01/2031		718,000		558,865
TOTAL BONDS				$	57,874,615
U.S. GOVERNMENT & GOVERNMENT AGENCY OBLIGATIONS —			Principal
9.02%			Amount		Value
U.S. Treasury - 9.02%
	3.63%, 05/15/2053	$	1,039,200	$	860,425
	3.88%, 08/15/2033		1,512,900		1,429,454
	3.38%, 05/15/2033		3,128,100		2,836,796
	4.13%, 11/15/2032		747,800		721,218
TOTAL U.S. GOVERNMENT & GOVERNMENT AGENCY OBLIGATIONS				$	5,847,893
INVESTMENT COMPANIES — 2.20%			Shares Held		Value
Money Market Funds — 2.20%
Principal Government Money Market Fund — Class R-6 5.26% ^(d),(e),(f)			125,603	$	125,603
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(f)			1,299,985		1,299,985
TOTAL INVESTMENT COMPANIES				$	1,425,588
Total Investments				$	65,148,096
Other Assets and Liabilities — (0.48)%					(312,939)
Total Net Assets — 100.00%				$	64,835,157

^(a)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in
	transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these
	securities totaled $6,027,181 or 9.30% of net assets.
^(b)	Rate shown is as of period end. The rate may be a variable or floating rate or a fixed rate which may convert to a variable or
	floating rate in the future.
^(c)	Security or a portion of the security was on loan. At the end of the period, the value of these securities totaled $123,226 or
	0.19% of net assets.




See accompanying notes.		39


			Schedule of Investments
	Principal Investment Grade Corporate Active ETF
			September 30, 2023 (unaudited)

^(d)	Affiliated Security. Security is either an affiliate (and registered under the Investment Company Act of 1940) or an affiliate
	as defined by the Investment Company Act of 1940 (controls 5.00% or more of the outstanding voting shares of the security).
	Please see Affiliated Securities sub-schedule for transactional information.
^(e)	Security or a portion of the security was received as collateral for securities lending. At the end of the period, the value of
	these securities totaled $125,603 or 0.19% of net assets.
^(f)	1-day yield shown as of period end.

	Portfolio Summary
Sector				Percent
Financial					23.73	%
Consumer, Non-cyclical					21.31	%
Utilities					14.17	%
Government					9.02	%
Technology					7.63	%
Communications					6.96	%
Industrial					6.39	%
Energy					4.40	%
Consumer, Cyclical					3.89	%
Money Market Funds					2.20	%
Basic Materials					0.78	%
Other Assets and Liabilities					(0.48	)%
TOTAL NET ASSETS					100.00	%

			June 30, 2023	Purchases					Sales		September 30, 2023
Affiliated Securities			Value		Cost			Proceeds				Value
Principal Government Money
Market Fund — Class R-6 5.26%		$	384,880	$	2,149,815			$	2,409,092		$	125,603
		$	384,880	$	2,149,815			$	2,409,092		$	125,603

							Realized Gain
					Realized				from			Change in
				Gain/(Loss) on				Capital Gain				Unrealized
			Income ^(a)	Investments			Distributions					Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%		$	—	$	—			$	—		$	—
		$	—	$	—			$	—		$	—

^(a)	Amount excludes earnings from securities lending collateral.

			Futures Contracts
											Value and Unrealized
									Notional			Appreciation/
Description and Expiration Date			Type		Contracts				Amount			(Depreciation)
U.S. 10 Year CBT; December 2023			Short				9	$	989,513	$		16,950
U.S. 10 Year Ultra; December 2023			Short				7		802,962			22,024
U.S. 5 Year CBT; December 2023			Short				13		1,375,201			5,529
U.S. Long Bond CBT; December 2023			Long				5		599,893			(30,987	)
U.S. Ultra Bond CBT; December 2023			Long				9		1,129,033			(60,845	)
Total									$			(47,329	)




See accompanying notes.				40


	Schedule of Investments
	Principal Millennial Global Growth ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.42%	Shares Held		Value

Apparel — 6.14%
adidas AG	648	$	114,151
Carter's, Inc.	739		51,102
Columbia Sportswear Co.	752		55,723
Fila Holdings Corp.	2,829		75,683
Gildan Activewear, Inc.	1,916		53,703
Kering SA	242		110,504
Levi Strauss & Co., Class A	3,436		46,661
LVMH Moet Hennessy Louis Vuitton SE	217		164,359
NIKE, Inc., Class B	1,041		99,541
PVH Corp.	885		67,711
Ralph Lauren Corp.	599		69,538
SMCP SA ^(a),(b)	9,676		39,283
Torrid Holdings, Inc. ^(a)	11,206		24,765
Urban Outfitters, Inc. ^(a)	24,948		815,550
VF Corp.	2,460		43,468
		$	1,831,742

Beverages — 1.94%
Brown-Forman Corp., Class B	2,119		122,245
Constellation Brands, Inc., Class A	619		155,573
Fevertree Drinks PLC	3,150		46,120
Monster Beverage Corp. ^(a)	3,564		188,714
Treasury Wine Estates Ltd.	8,548		67,765
		$	580,417

Building Materials — 1.13%
Fortune Brands Innovations, Inc.	1,906		118,477
Masco Corp.	2,785		148,858
Masterbrand, Inc. ^(a)	1,906		23,158
Mohawk Industries, Inc. ^(a)	546		46,852
		$	337,345

Commercial Services — 1.79%
Aaron's Co., Inc.	3,380		35,388
Adyen NV ^(a),(b)	302		225,323
Global Payments, Inc.	1,030		118,852
GMO Payment Gateway, Inc.	700		38,302
Nuvei Corp. ^(b)	986		14,790
Paysafe Ltd. ^(a)	1,828		21,918
PROG Holdings, Inc. ^(a)	2,358		78,309
		$	532,882

Computers — 0.46%
Apple, Inc.	811		138,851

Diversified Financial Services — 8.16%
Coinbase Global, Inc., Class A ^(a)	4,387		329,376
Discover Financial Services	7,581		656,742
Futu Holdings Ltd., ADR ^(a)	14,026		810,843
LexinFintech Holdings Ltd., ADR	174,121		384,807
Lufax Holding Ltd., ADR	81,690		86,591
Rocket Cos., Inc., Class A ^(a)	6,106		49,947
XP, Inc., Class A	5,111		117,809
		$	2,436,115

Entertainment — 6.95%
CTS Eventim AG & Co. KGaA	6,659		379,117
DraftKings, Inc., Class A ^(a)	3,491		102,775

See accompanying notes.


Schedule of Investments
Principal Millennial Global Growth ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Entertainment (continued)
HYBE Co. Ltd. ^(a)	2,691	$	474,624
Universal Music Group NV	22,757		595,000
Warner Music Group Corp., Class A	16,638		522,433
		$	2,073,949

Food — 2.81%
Albertsons Cos., Inc., Class A	4,258		96,869
Kroger Co.	14,553		651,247
Sprouts Farmers Market, Inc. ^(a)	2,126		90,993
		$	839,109

Home Builders — 1.05%
DR Horton, Inc.	1,924		206,772
Toll Brothers, Inc.	1,444		106,798
		$	313,570

Home Furnishings — 2.30%
Arhaus, Inc. ^(a)	7,979		74,205
Sleep Number Corp. ^(a)	1,339		32,926
Sony Group Corp.	5,800		475,053
Tempur Sealy International, Inc.	2,431		105,360
		$	687,544

Internet — 30.63%
AfreecaTV Co. Ltd.	5,627		350,697
Alphabet, Inc., Class C ^(a)	5,980		788,463
Bilibili, Inc., ADR ^(a)	18,036		248,356
D-MARKET Elektronik Hizmetler ve Ticaret A/S, ADR ^(a)	32,742		43,547
eBay, Inc.	2,472		108,990
Expedia Group, Inc. ^(a)	2,837		292,409
Farfetch Ltd., Class A ^(a)	4,918		10,279
Hello Group, Inc., ADR	79,070		551,909
iQIYI, Inc., ADR ^(a)	100,567		476,687
JD.com, Inc., ADR	2,759		80,370
JOYY, Inc., ADR	18,652		710,828
Kakao Corp.	1,773		57,747
Kuaishou Technology ^(a),(b)	64,500		517,667
Lulu's Fashion Lounge Holdings, Inc. ^(a)	10,017		20,134
Match Group, Inc. ^(a)	5,102		199,871
Meituan, Class B ^(a),(b)	280		4,098
Meta Platforms, Inc., Class A ^(a)	641		192,435
Naspers Ltd., Class N	5,353		855,391
Netflix, Inc. ^(a)	2,231		842,426
Pinterest, Inc., Class A ^(a)	5,728		154,828
RealReal, Inc. ^(a)	9,355		19,739
Revolve Group, Inc. ^(a)	11,630		158,284
Rightmove PLC	8,921		61,193
Shutterstock, Inc.	732		27,853
Snap, Inc., Class A ^(a)	15,373		136,973
Temple & Webster Group Ltd. ^(a)	14,794		57,071
Tencent Holdings Ltd.	3,300		129,034
Tencent Music Entertainment Group, ADR ^(a)	140,833		898,514
THG PLC ^(a)	61,361		52,287
Trip.com Group Ltd., ADR ^(a)	26,366		922,019
Vipshop Holdings Ltd., ADR ^(a)	8,256		132,178
Weibo Corp., ADR	3,031		38,009
		$	9,140,286

See accompanying notes.


	Schedule of Investments
Principal Millennial Global Growth ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Leisure Time — 1.85%
Camping World Holdings, Inc., Class A	22,402	$	457,225
Shimano, Inc.	700		94,456
		$	551,681

Media — 3.83%
Comcast Corp., Class A	3,028		134,262
Fox Corp., Class B	3,876		111,939
Paramount Global, Class B	14,866		191,771
Sirius XM Holdings, Inc.	21,435		96,886
Vivendi SE	69,355		608,309
		$	1,143,167

Real Estate — 0.51%
REA Group Ltd.	1,526		151,410

REITs — 3.00%
EastGroup Properties, Inc.	691		115,072
Equity Residential	1,562		91,705
Prologis, Inc.	875		98,184
Rexford Industrial Realty, Inc.	1,885		93,025
Segro PLC	51,710		453,879
Warehouses De Pauw CVA	1,708		42,328
		$	894,193

Retail — 17.21%
Academy Sports & Outdoors, Inc.	1,670		78,941
American Eagle Outfitters, Inc.	4,040		67,104
ANTA Sports Products Ltd.	12,400		139,582
Bath & Body Works, Inc.	2,939		99,338
Dick's Sporting Goods, Inc.	658		71,446
Foot Locker, Inc.	2,291		39,749
Frasers Group PLC ^(a)	8,905		87,518
Goldwin, Inc.	1,400		94,995
H & M Hennes & Mauritz AB, Class B	11,474		163,264
Hibbett, Inc.	1,487		70,647
Home Depot, Inc.	2,790		843,026
Industria de Diseno Textil SA	38,468		1,435,255
Kingfisher PLC	22,106		60,227
Li Ning Co. Ltd.	17,771		74,774
Lowe's Cos., Inc.	705		146,527
Lululemon Athletica, Inc. ^(a)	390		150,388
Next PLC	1,976		175,901
Pandora A/S	1,620		168,006
Petco Health & Wellness Co., Inc. ^(a)	3,468		14,184
Qurate Retail, Inc., Series A ^(a)	14,266		8,654
Ryohin Keikaku Co. Ltd.	6,150		79,653
Signet Jewelers Ltd.	9,425		676,809
Starbucks Corp.	1,548		141,286
Truworths International Ltd.	18,615		75,212
Victoria's Secret & Co. ^(a)	1,321		22,034
Williams-Sonoma, Inc.	972		151,049
		$	5,135,569

Semiconductors — 0.77%
NVIDIA Corp.	526		228,805

Software — 3.77%
DouYu International Holdings Ltd., ADR ^(a)	221,815		215,959

See accompanying notes.


		Schedule of Investments
	Principal Millennial Global Growth ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value
Software (continued)
Fidelity National Information Services, Inc.		1,412	$	78,041
Fiserv, Inc. ^(a)		1,391		157,127
HUYA, Inc., ADR ^(a)		102,011		289,711
Kakao Games Corp. ^(a)		1,068		20,143
Microsoft Corp.		462		145,877
NetEase, Inc., ADR		1,736		173,878
XD, Inc. ^(a)		23,800		43,157
			$	1,123,893

Telecommunications — 2.35%
AT&T, Inc.		46,800		702,936
Toys, Games & Hobbies — 0.93%
Funko, Inc., Class A ^(a)		36,240		277,236
Transportation — 1.84%
Deutsche Post AG		3,198		130,290
FedEx Corp.		614		162,661
RXO, Inc. ^(a)		931		18,368
United Parcel Service, Inc., Class B		663		103,342
XPO, Inc. ^(a)		931		69,508
Yamato Holdings Co. Ltd.		4,000		65,177
			$	549,346
TOTAL COMMON STOCKS			$	29,670,046
INVESTMENT COMPANIES — 0.49%		Shares Held		Value
Money Market Fund — 0.49%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(c)		146,654	$	146,654
TOTAL INVESTMENT COMPANIES			$	146,654
Total Investments			$	29,816,700
Other Assets and Liabilities — 0.09%				26,103
Total Net Assets — 100.00%			$	29,842,803

^(a)	Non-income producing security.
^(b)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in
	transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these
	securities totaled $801,161 or 2.68% of net assets.
^(c)	1-day yield shown as of period end.




See accompanying notes.		44


		Schedule of Investments
		Principal Millennial Global Growth ETF
		September 30, 2023 (unaudited)

Portfolio Summary
Location			Percent
United States				48.02	%
China				18.12	%
Spain				4.81	%
Republic Of Korea				3.28	%
United Kingdom				3.25	%
South Africa				3.12	%
France				3.09	%
Japan				2.84	%
Netherlands				2.75	%
Hong Kong				2.72	%
Singapore				2.38	%
Germany				2.09	%
Australia				0.92	%
Canada				0.73	%
Denmark				0.56	%
Sweden				0.55	%
Brazil				0.39	%
Turkey				0.15	%
Belgium				0.14	%
Other Assets and Liabilities				0.09	%
TOTAL NET ASSETS				100.00	%

		June 30, 2023	Purchases				Sales		September 30, 2023
Affiliated Securities		Value		Cost			Proceeds		Value
Principal Government Money
Market Fund — Class R-6 5.26%	$	721,539	$	1,186,923		$	1,908,462	$	—
	$	721,539	$	1,186,923		$	1,908,462	$	—

						Realized Gain
				Realized			from		Change in
			Gain/(Loss) on			Capital Gain			Unrealized
		Income ^(a)	Investments			Distributions			Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%	$	—	$	—		$	—	$	—
	$	—	$	—		$	—	$	—

^(a)Amount excludes earnings from securities lending collateral.

See accompanying notes.


Schedule of Investments
Principal Quality ETF
September 30, 2023 (unaudited)

COMMON STOCKS — 99.58%	Shares Held		Value
Beverages — 1.02%
Keurig Dr Pepper, Inc.	12,365	$	390,363
Biotechnology — 1.62%
Amgen, Inc.	2,299		617,879
Building Materials — 1.32%
Trane Technologies PLC	2,494		506,057
Commercial Services — 2.06%
Automatic Data Processing, Inc.	2,319		557,905
MarketAxess Holdings, Inc.	1,064		227,313
		$	785,218

Computers — 8.53%
Accenture PLC, Class A	2,263		694,990
Apple, Inc.	12,542		2,147,316
Leidos Holdings, Inc.	4,512		415,826
		$	3,258,132

Distribution/Wholesale — 3.28%
LKQ Corp.	7,583		375,435
Pool Corp.	1,209		430,525
WW Grainger, Inc.	648		448,312
		$	1,254,272

Diversified Financial Services — 2.11%
Mastercard, Inc., Class A	2,040		807,656
Electrical Components & Equipment — 2.63%
AMETEK, Inc.	3,175		469,138
Emerson Electric Co.	5,554		536,350
		$	1,005,488

Electronics — 2.78%
Agilent Technologies, Inc.	3,285		367,329
Keysight Technologies, Inc. ^(a)	2,763		365,572
Mettler-Toledo International, Inc. ^(a)	296		327,989
		$	1,060,890

Healthcare — Products — 9.12%
Abbott Laboratories	5,960		577,226
Danaher Corp.	2,336		579,562
Edwards Lifesciences Corp. ^(a)	5,610		388,661
Stryker Corp.	1,807		493,799
Thermo Fisher Scientific, Inc.	1,150		582,095
Waters Corp. ^(a)	1,399		383,620
West Pharmaceutical Services, Inc.	1,278		479,518
		$	3,484,481

Healthcare — Services — 5.91%
Charles River Laboratories International, Inc. ^(a)	2,125		416,458
Humana, Inc.	939		456,842
IQVIA Holdings, Inc. ^(a)	2,292		450,951
UnitedHealth Group, Inc.	1,847		931,239
		$	2,255,490

Home Builders — 2.68%
DR Horton, Inc.	4,434		476,522

See accompanying notes.


	Schedule of Investments
	Principal Quality ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value
Home Builders (continued)
PulteGroup, Inc.		7,369	$	545,674
			$	1,022,196

Household Products/Wares — 1.19%
Avery Dennison Corp.		2,487		454,300
Insurance — 4.45%
Aon PLC, Class A		1,567		508,053
Arthur J Gallagher & Co.		2,432		554,326
Berkshire Hathaway, Inc., Class B ^(a)		137		47,991
Marsh & McLennan Cos., Inc.		3,094		588,788
			$	1,699,158

Internet — 4.92%
Alphabet, Inc., Class A ^(a)		1,199		156,901
Alphabet, Inc., Class C ^(a)		5,549		731,636
Amazon.com, Inc. ^(a)		4,209		535,048
CDW Corp.		2,268		457,592
			$	1,881,177

Machinery — Diversified — 2.22%
IDEX Corp.		1,915		398,358
Nordson Corp.		2,015		449,688
			$	848,046

Pharmaceuticals — 4.84%
AbbVie, Inc.		4,468		666,000
Merck & Co., Inc.		6,529		672,161
Zoetis, Inc.		2,928		509,413
			$	1,847,574

Pipelines — 1.36%
Williams Cos., Inc.		15,416		519,365
Retail — 4.32%
Genuine Parts Co.		2,588		373,655
O'Reilly Automotive, Inc. ^(a)		565		513,506
Ulta Beauty, Inc. ^(a)		842		336,337
Yum! Brands, Inc.		3,416		426,795
			$	1,650,293

Semiconductors — 15.90%
Analog Devices, Inc.		2,692		471,342
Applied Materials, Inc.		4,161		576,090
Broadcom, Inc.		1,076		893,704
Microchip Technology, Inc.		5,534		431,929
NVIDIA Corp.		4,181		1,818,693
NXP Semiconductors NV		2,531		505,998
ON Semiconductor Corp. ^(a)		5,563		517,081
QUALCOMM, Inc.		4,480		497,549
Skyworks Solutions, Inc.		3,670		361,825
			$	6,074,211

Software — 14.45%
Adobe, Inc. ^(a)		1,598		814,820
Fiserv, Inc. ^(a)		4,372		493,861
Intuit, Inc.		1,265		646,339
Microsoft Corp.		6,092		1,923,549

See accompanying notes.


		Schedule of Investments
		Principal Quality ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)				Shares Held		Value
Software (continued)
MSCI, Inc.				828	$	424,830
Salesforce, Inc. ^(a)				3,218		652,546
Synopsys, Inc. ^(a)				1,223		561,321
					$	5,517,266

Telecommunications — 1.73%
Cisco Systems, Inc.				12,308		661,678
Transportation — 1.14%
Norfolk Southern Corp.				2,202		433,640
TOTAL COMMON STOCKS					$	38,034,830
INVESTMENT COMPANIES — 0.38%				Shares Held		Value
Money Market Fund — 0.38%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)				143,805	$	143,805
TOTAL INVESTMENT COMPANIES					$	143,805
Total Investments					$	38,178,635
Other Assets and Liabilities — 0.04%						14,477
Total Net Assets — 100.00%					$	38,193,112

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Technology		38.88	%
Consumer, Non-cyclical		25.75	%
Consumer, Cyclical		10.28	%
Industrial		10.09	%
Communications		6.66	%
Financial		6.56	%
Energy		1.36	%
Money Market Fund		0.38	%
Other Assets and Liabilities		0.04	%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		48


	Schedule of Investments
Principal Real Estate Active Opportunities ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 97.22%	Shares Held			Value

Entertainment — 1.89%
Marriott Vacations Worldwide Corp.	949		$	95,498

REITs — 95.33%
Alexandria Real Estate Equities, Inc.	1,614			161,561
American Homes 4 Rent, Class A	7,076			238,391
American Tower Corp.	2,067			339,918
Crown Castle, Inc.	1,980			182,219
CubeSmart	2,131			81,255
DiamondRock Hospitality Co.	12,380			99,411
Digital Realty Trust, Inc.	1,935			234,174
Equinix, Inc.	333			241,845
Equity LifeStyle Properties, Inc.	2,622			167,048
Extra Space Storage, Inc.	2,602			316,351
Gaming & Leisure Properties, Inc.	5,036			229,390
Invitation Homes, Inc.	10,526			333,569
National Health Investors, Inc.	3,125			160,500
Rexford Industrial Realty, Inc.	6,784			334,790
Sabra Health Care REIT, Inc.	14,061			196,010
SBA Communications Corp.	846			169,344
Sun Communities, Inc.	2,503			296,205
Terreno Realty Corp.	3,241			184,089
Ventas, Inc.	8,844			372,598
VICI Properties, Inc.	8,071			234,866
Welltower, Inc.	2,912			238,551
			$	4,812,085
TOTAL COMMON STOCKS			$	4,907,583
INVESTMENT COMPANIES — 2.40%	Shares Held			Value

Money Market Fund — 2.40%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(a)	120,917		$	120,917
TOTAL INVESTMENT COMPANIES			$	120,917
Total Investments			$	5,028,500
Other Assets and Liabilities — 0.38%				19,431

Total Net Assets — 100.00%			$	5,047,931

^(a)1-day yield shown as of period end.

Portfolio Summary
Sector	Percent
Financial	95.33	%
Money Market Fund	2.40	%
Consumer, Cyclical	1.89	%
Other Assets and Liabilities	0.38	%
TOTAL NET ASSETS	100.00	%




See accompanying notes.	49


Schedule of Investments
Principal Spectrum Preferred Securities Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS — 97.12%		Amount		Value

Banks — 48.82%
Bank of America Corp.
(5-year Treasury Constant Maturity Rate + 2.76%),
4.38%, 01/27/2027 ^(a),(b)	$	15,731,000	$	13,183,347
(5-year Treasury Constant Maturity Rate + 3.23%),
6.13%, 04/27/2027 ^(a),(b),(c)		11,025,000		10,563,304
Bank of Montreal
(5-year Treasury Constant Maturity Rate + 2.98%),
4.80%, 08/25/2024 ^(a),(b)		3,362,000		3,009,351
Bank of New York Mellon Corp.
(5-year Treasury Constant Maturity Rate + 3.35%),
3.70%, 03/20/2026 ^(a),(b)		11,569,000		10,374,140
(5-year Treasury Constant Maturity Rate + 2.63%),
3.75%, 12/20/2026 ^(a),(b)		3,532,000		2,864,782
Bank of Nova Scotia
(5-year Treasury Constant Maturity Rate + 4.55%),
4.90%, 06/04/2025 ^(a),(b)		8,965,000		8,199,532
(5-year Treasury Constant Maturity Rate + 4.39%),
8.63%, 10/27/2082 ^(a)		12,727,000		12,692,903
Citigroup, Inc.
(5-year Treasury Constant Maturity Rate + 3.42%),
3.88%, 02/18/2026 ^(a),(b)		11,262,000		9,610,344
(5-year Treasury Constant Maturity Rate + 3.60%),
4.00%, 12/10/2025 ^(a),(b)		13,286,000		11,621,945
(5-year Treasury Constant Maturity Rate + 3.21%),
7.38%, 05/15/2028 ^(a),(b),(c)		7,530,000		7,306,547
Citizens Financial Group, Inc.
(5-year Treasury Constant Maturity Rate + 3.22%),
4.00%, 10/06/2026 ^(a),(b)		6,671,000		4,944,130
(5-year Treasury Constant Maturity Rate + 5.31%),
5.65%, 10/06/2025 ^(a),(b)		7,405,000		6,764,078
Goldman Sachs Group, Inc.
(5-year Treasury Constant Maturity Rate + 2.92%),
3.65%, 08/10/2026 ^(a),(b)		2,001,000		1,612,969
(5-year Treasury Constant Maturity Rate + 2.97%),
3.80%, 05/10/2026 ^(a),(b)		1,168,000		952,417
(5-year Treasury Constant Maturity Rate + 2.95%),
4.13%, 11/10/2026 ^(a),(b)		8,563,000		7,003,916
(5-year Treasury Constant Maturity Rate + 3.62%),
5.50%, 08/10/2024 ^(a),(b)		8,268,000		8,059,062
HSBC Capital Funding Dollar 1 LP
(3-month USD LIBOR + 4.98%),
10.18%, 06/30/2030 ^(a),(b)		6,021,000		7,338,967
Huntington Bancshares, Inc.
(7-year Treasury Constant Maturity Rate + 4.05%),
4.45%, 10/15/2027 ^(a),(b)		5,080,000		4,109,077
(10-year Treasury Constant Maturity Rate + 4.95%),
5.63%, 07/15/2030 ^(a),(b)		7,032,000		6,186,502
JPMorgan Chase & Co.
(5-year Treasury Constant Maturity Rate + 2.85%),
3.65%, 06/01/2026 ^(a),(b)		18,104,000		15,801,856
(3-month Term Secured Overnight Financing Rate + 4.04%),
6.75%, 02/01/2024 ^(a),(b)		7,791,000		7,789,441
M&T Bank Corp.
(5-year Treasury Constant Maturity Rate + 2.68%),
3.50%, 09/01/2026 ^(a),(b)		19,608,000		13,789,122
(5-year Treasury Constant Maturity Rate + 3.17%),
5.00%, 08/01/2024 ^(a),(b)		5,000,000		4,198,019

See accompanying notes.


Schedule of Investments
Principal Spectrum Preferred Securities Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Banks (continued)
PNC Financial Services Group, Inc.
(5-year Treasury Constant Maturity Rate + 2.60%),
3.40%, 09/15/2026 ^(a),(b)	$	7,196,000	$	5,323,410
(5-year Treasury Constant Maturity Rate + 3.24%),
6.20%, 09/15/2027 ^(a),(b)		13,480,000		12,388,190
(7-year Treasury Constant Maturity Rate + 2.81%),
6.25%, 03/15/2030 ^(a),(b)		10,290,000		8,820,738
Toronto-Dominion Bank
(5-year Treasury Constant Maturity Rate + 4.08%),
8.13%, 10/31/2082 ^(a)		22,267,000		22,152,412
Truist Financial Corp.
(5-year Treasury Constant Maturity Rate + 3.00%),
4.80%, 09/01/2024 ^(a),(b)		10,894,000		9,338,624
(5-year Treasury Constant Maturity Rate + 4.61%),
4.95%, 09/01/2025 ^(a),(b)		11,697,000		10,756,348
(3-month Term Secured Overnight Financing Rate + 3.36%),
8.77%, 12/15/2024 ^(b)		2,799,000		2,757,021
U.S. Bancorp
(5-year Treasury Constant Maturity Rate + 2.54%),
3.70%, 01/15/2027 ^(a),(b)		19,581,000		14,369,303
Wells Fargo & Co.
(5-year Treasury Constant Maturity Rate + 3.45%),
3.90%, 03/15/2026 ^(a),(b)		29,418,000		25,692,160
(5-year Treasury Constant Maturity Rate + 3.61%),
7.63%, 09/15/2028 ^(a),(b)		2,000,000		2,016,334
			$	291,590,291

Diversified Financial Services — 11.27%
American Express Co.
(5-year Treasury Constant Maturity Rate + 2.85%),
3.55%, 09/15/2026 ^(a),(b)		14,967,000		11,883,633
Capital One Financial Corp.
(5-year Treasury Constant Maturity Rate + 3.16%),
3.95%, 09/01/2026 ^(a),(b)		17,756,000		13,327,496
Charles Schwab Corp.
(5-year Treasury Constant Maturity Rate + 3.17%),
4.00%, 06/01/2026 ^(a),(b)		14,949,000		12,485,505
(5-year Treasury Constant Maturity Rate + 4.97%),
5.38%, 06/01/2025 ^(a),(b)		5,531,000		5,313,787
Discover Financial Services
(5-year Treasury Constant Maturity Rate + 5.78%),
6.13%, 06/23/2025 ^(a),(b),(c)		10,641,000		10,227,760
Voya Financial, Inc.
(5-year Treasury Constant Maturity Rate + 3.36%),
7.75%, 09/15/2028 ^(a),(b)		13,990,000		14,088,657
			$	67,326,838

Electric — 13.24%
Algonquin Power & Utilities Corp.
(5-year Treasury Constant Maturity Rate + 3.25%),
4.75%, 01/18/2082 ^(a)		2,010,000		1,638,150
American Electric Power Co., Inc.
(5-year Treasury Constant Maturity Rate + 2.68%),
3.88%, 02/15/2062 ^(a)		9,601,000		7,813,272
CMS Energy Corp.
(5-year Treasury Constant Maturity Rate + 4.12%),
4.75%, 06/01/2050 ^(a)		2,549,000		2,174,450

See accompanying notes.


Schedule of Investments
Principal Spectrum Preferred Securities Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Electric (continued)
Dominion Energy, Inc.
(5-year Treasury Constant Maturity Rate + 3.20%),
4.35%, 01/15/2027 ^(a),(b)	$	1,185,000	$	1,023,143
(5-year Treasury Constant Maturity Rate + 2.99%),
4.65%, 12/15/2024 ^(a),(b)		11,434,000		10,466,239
Duke Energy Corp.
(5-year Treasury Constant Maturity Rate + 2.32%),
3.25%, 01/15/2082 ^(a)		12,439,000		9,164,432
(5-year Treasury Constant Maturity Rate + 3.39%),
4.88%, 09/16/2024 ^(a),(b)		14,341,000		13,957,926
Emera, Inc.
(3-month USD LIBOR + 5.44%),
6.75%, 06/15/2076 ^(a)		2,878,000		2,762,780
NextEra Energy Capital Holdings, Inc.
(5-year Treasury Constant Maturity Rate + 2.55%),
3.80%, 03/15/2082 ^(a)		15,794,000		13,369,668
Southern Co.
(5-year Treasury Constant Maturity Rate + 3.73%),
4.00%, 01/15/2051 ^(a)		18,095,000		16,737,556
			$	79,107,616

Hand/Machine Tools — 0.39%
Stanley Black & Decker, Inc.
(5-year Treasury Constant Maturity Rate + 2.66%),
4.00%, 03/15/2060 ^(a)		2,816,000		2,340,813

Insurance — 14.80%
Allianz SE
(5-year Treasury Constant Maturity Rate + 3.23%),
6.35%, 09/06/2053		5,000,000		4,827,090
Allstate Corp.
(3-month Term Secured Overnight Financing Rate + 3.20%),
8.56%, 08/15/2053		3,251,000		3,208,050
American International Group, Inc.
(3-month USD LIBOR + 2.87%),
5.75%, 04/01/2048 ^(a)		1,376,000		1,274,807
Argentum Netherlands BV for Swiss Re Ltd.
(3-month USD LIBOR + 3.78%),
5.63%, 08/15/2052 ^(a)		5,600,000		5,243,000
Argentum Netherlands BV for Zurich Insurance Co. Ltd.
(5-year Treasury Constant Maturity Rate + 3.27%),
5.13%, 06/01/2048 ^(a)		4,000,000		3,720,600
Cloverie PLC for Zurich Insurance Co. Ltd.
(3-month USD LIBOR + 4.92%),
5.63%, 06/24/2046 ^(a)		5,600,000		5,413,632
Corebridge Financial, Inc.
(5-year Treasury Constant Maturity Rate + 3.85%),
6.88%, 12/15/2052 ^(a)		7,921,000		7,588,238
Equitable Holdings, Inc.
(5-year Treasury Constant Maturity Rate + 4.74%),
4.95%, 09/15/2025 ^(a),(b)		3,612,000		3,399,474
Liberty Mutual Group, Inc.
(5-year Treasury Constant Maturity Rate + 3.32%),
4.13%, 12/15/2051 ^(a),(d)		7,182,000		5,904,574
Meiji Yasuda Life Insurance Co.
(5-year Swap rate + 4.23%),
5.20%, 10/20/2045 ^(a),(d)		3,210,000		3,124,238

See accompanying notes.


Schedule of Investments
Principal Spectrum Preferred Securities Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Insurance (continued)
MetLife, Inc.
(5-year Treasury Constant Maturity Rate + 3.58%),
3.85%, 09/15/2025 ^(a),(b)	$	12,376,000	$	11,448,879
9.25%, 04/08/2068 ^(d)		2,534,000		2,846,275
Nippon Life Insurance Co.
(5-year Treasury Constant Maturity Rate + 2.65%),
2.75%, 01/21/2051 ^(a),(d)		4,958,000		3,900,099
(5-year Treasury Constant Maturity Rate + 2.60%),
2.90%, 09/16/2051 ^(a),(d)		3,509,000		2,750,319
Prudential Financial, Inc.
(5-year Treasury Constant Maturity Rate + 3.04%),
3.70%, 10/01/2050 ^(a)		14,198,000		11,547,030
(5-year Treasury Constant Maturity Rate + 3.16%),
5.13%, 03/01/2052 ^(a)		4,976,000		4,285,054
Sumitomo Life Insurance Co.
(5-year Treasury Constant Maturity Rate + 2.75%),
3.38%, 04/15/2081 ^(a),(d)		4,030,000		3,349,271
Zurich Finance Ireland Designated Activity Co.
(5-year Treasury Constant Maturity Rate + 2.78%),
3.00%, 04/19/2051 ^(a)		6,000,000		4,575,360
			$	88,405,990

Oil & Gas — 1.42%
BP Capital Markets PLC
(5-year Treasury Constant Maturity Rate + 4.04%),
4.38%, 06/22/2025 ^(a),(b)		5,982,000		5,704,676
(5-year Treasury Constant Maturity Rate + 4.40%),
4.88%, 03/22/2030 ^(a),(b)		3,121,000		2,788,375
			$	8,493,051

Pipelines — 5.63%
Enbridge, Inc.
(5-year Treasury Constant Maturity Rate + 5.31%),
5.75%, 07/15/2080 ^(a)		2,485,000		2,163,095
(3-month Term Secured Overnight Financing Rate + 4.15%),
6.00%, 01/15/2077 ^(a)		4,882,000		4,469,593
(5-year Treasury Constant Maturity Rate + 4.42%),
7.63%, 01/15/2083 ^(a)		6,949,000		6,635,302
Enterprise Products Operating LLC
(3-month Term Secured Overnight Financing Rate + 3.29%),
5.25%, 08/16/2077 ^(a)		4,625,000		4,069,924
Transcanada Trust
(6-month Secured Overnight Financing Rate + 4.42%),
5.50%, 09/15/2079 ^(a)		5,233,000		4,296,688
(5-year Treasury Constant Maturity Rate + 3.99%),
5.60%, 03/07/2082 ^(a)		14,686,000		12,020,864
			$	33,655,466

REITs — 0.50%
Scentre Group Trust 2
(5-year Treasury Constant Maturity Rate + 4.38%),
4.75%, 09/24/2080 ^(a),(d)		1,210,000		1,086,655
(5-year Treasury Constant Maturity Rate + 4.69%),
5.13%, 09/24/2080 ^(a),(d)		2,249,000		1,877,108
			$	2,963,763

See accompanying notes.


	Schedule of Investments
	Principal Spectrum Preferred Securities Active ETF
	September 30, 2023 (unaudited)

				Principal
BONDS (continued)				Amount		Value

Telecommunications — 1.05%
Vodafone Group PLC
	(5-year Treasury Constant Maturity Rate + 2.77%),
	4.13%, 06/04/2081 ^(a)	$		993,000	$	766,725
	(5-year Swap rate + 4.87%),
	7.00%, 04/04/2079 ^(a)			5,518,000		5,480,520
					$	6,247,245
TOTAL BONDS					$	580,131,073
INVESTMENT COMPANIES — 1.92%				Shares Held		Value

Money Market Funds — 1.92%
Principal Government Money Market Fund — Class R-6 5.26% ^(e),(f),(g)				3,546,785	$	3,546,785
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(g)				7,904,976		7,904,976
TOTAL INVESTMENT COMPANIES					$	11,451,761
Total Investments					$	591,582,834
Other Assets and Liabilities — 0.96%						5,720,767

Total Net Assets — 100.00%					$	597,303,601

^(a)	Rate shown is as of period end. The rate may be a variable or floating rate or a fixed rate which may convert to a variable or
	floating rate in the future.
^(b)	Perpetual security. Perpetual securities pay an indefinite stream of interest, but they may be called by the issuer at an earlier
	date. Date shown, if any, reflects the next call date or final legal maturity date. Rate shown is as of period end.
^(c)	Security or a portion of the security was on loan. At the end of the period, the value of these securities totaled $3,480,699 or
	0.58% of net assets.
^(d)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in
	transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these
	securities totaled $24,838,539 or 4.16% of net assets.
^(e)	Affiliated Security. Security is either an affiliate (and registered under the Investment Company Act of 1940) or an affiliate
	as defined by the Investment Company Act of 1940 (controls 5.00% or more of the outstanding voting shares of the security).
	Please see Affiliated Securities sub-schedule for transactional information.
^(f)	Security or a portion of the security was received as collateral for securities lending. At the end of the period, the value of
	these securities totaled $3,546,785 or 0.59% of net assets.
^(g)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Financial		75.39	%
Utilities		13.24	%
Energy		7.06	%
Money Market Funds		1.92	%
Communications		1.04	%
Industrial		0.39	%
Other Assets and Liabilities		0.96	%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		54


		Schedule of Investments
	Principal Spectrum Preferred Securities Active ETF
		September 30, 2023 (unaudited)

		June 30, 2023	Purchases			Sales		September 30, 2023
Affiliated Securities		Value		Cost		Proceeds		Value
Principal Government Money
Market Fund — Class R-6 5.26%	$	3,970,623	$	27,944,850	$	28,368,688	$	3,546,785
	$	3,970,623	$	27,944,850	$	28,368,688	$	3,546,785

					Realized Gain
				Realized		from		Change in
			Gain/(Loss) on		Capital Gain			Unrealized
		Income ^(a)	Investments		Distributions			Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%	$	—	$	—	$	—	$	—
	$	—	$	—	$	—	$	—

^(a)Amount excludes earnings from securities lending collateral.

See accompanying notes.


Schedule of Investments
Principal Spectrum Tax-Advantaged Dividend Active ETF
September 30, 2023 (unaudited)

PREFERRED STOCKS — 10.23%		Shares Held		Value

Banks — 3.80%
Bank of America Corp.; Series NN
4.38%, 11/03/2025 ^(a)		4,380	$	77,132
Morgan Stanley; Series I
(3-month USD LIBOR + 3.71%),
6.38%, 10/15/2024 ^(a)		17,030		422,344
Morgan Stanley; Series P
6.50%, 10/15/2027 ^(a)		4,000		100,560
State Street Corp.; Series D
(3-month USD LIBOR + 3.11%),
5.90%, 03/15/2024 ^(a)		6,410		160,634
			$	760,670

Insurance — 3.80%
Allstate Corp.; Series H
5.10%, 10/15/2024 ^(a)		11,500		224,710
American International Group, Inc.; Series A
5.85%, 03/15/2024 ^(a)		8,019		186,682
MetLife, Inc.; Series F
4.75%, 03/15/2025 ^(a)		17,250		350,003
			$	761,395

Telecommunications — 2.63%
AT&T, Inc.; Series A
5.00%, 12/12/2024 ^(a)		11,381		230,124
AT&T, Inc.; Series C
4.75%, 02/18/2025 ^(a)		15,395		295,276
			$	525,400
TOTAL PREFERRED STOCKS			$	2,047,465
		Principal
BONDS — 87.81%		Amount		Value

Banks — 70.09%
Bank of America Corp.
(3-month Term Secured Overnight Financing Rate + 4.81%),
6.30%, 03/10/2026 ^(a),(b)	$	575,000	$	564,127
Bank of New York Mellon Corp.
(5-year Treasury Constant Maturity Rate + 3.35%),
3.70%, 03/20/2026 ^(a),(b)		230,000		206,245
(5-year Treasury Constant Maturity Rate + 4.36%),
4.70%, 09/20/2025 ^(a),(b)		275,000		264,704
Bank of Nova Scotia
(5-year Treasury Constant Maturity Rate + 4.55%),
4.90%, 06/04/2025 ^(a),(b)		575,000		525,904
(5-year Treasury Constant Maturity Rate + 4.39%),
8.63%, 10/27/2082 ^(b)		300,000		299,196
BNP Paribas SA
(5-year Treasury Constant Maturity Rate + 4.90%),
7.75%, 08/16/2029 ^{(a),(b),(c),(d)}		200,000		189,853
Citigroup, Inc.
(5-year Treasury Constant Maturity Rate + 3.42%),
3.88%, Series X; 02/18/2026 ^(a),(b)		655,000		558,939
Citizens Financial Group, Inc.
(5-year Treasury Constant Maturity Rate + 5.31%),
5.65%, 10/06/2025 ^(a),(b)		575,000		525,232
Credit Agricole SA
(5-year Swap Rate + 4.90%),
7.88%, 01/23/2024 ^(a),(b),(d)		861,000		854,543

See accompanying notes.


Schedule of Investments
Principal Spectrum Tax-Advantaged Dividend Active ETF
September 30, 2023 (unaudited)

		Principal
BONDS (continued)		Amount		Value

Banks (continued)
Fifth Third Bancorp
(5-year Treasury Constant Maturity Rate + 4.22%),
4.50%, 09/30/2025 ^(a),(b)	$	548,000	$	490,777
Goldman Sachs Group, Inc.
(5-year Treasury Constant Maturity Rate + 2.92%),
3.65%, Series U; 08/10/2026 ^(a),(b)		585,000		471,558
HSBC Holdings PLC
(5-year Swap Rate + 4.37%),
6.38%, 03/30/2025 ^(a),(b),(d)		861,000		827,081
Huntington Bancshares, Inc.
(10-year Treasury Constant Maturity Rate + 4.95%),
5.63%, 07/15/2030 ^(a),(b)		575,000		505,864
ING Groep NV
(5-year Treasury Constant Maturity Rate + 4.34%),
5.75%, 11/16/2026 ^(a),(b),(d)		861,000		762,468
JPMorgan Chase & Co.
(5-year Treasury Constant Maturity Rate + 2.85%),
3.65%, 06/01/2026 ^(a),(b)		110,000		96,012
Lloyds Banking Group PLC
(5-year Swap Rate + 4.50%),
7.50%, 09/27/2025 ^(a),(b),(d)		861,000		804,412
M&T Bank Corp.
(5-year Treasury Constant Maturity Rate + 2.68%),
3.50%, 09/01/2026 ^(a),(b)		300,000		210,972
(3-month USD LIBOR + 3.52%),
5.13%, 11/01/2026 ^(a),(b)		247,000		202,315
NatWest Group PLC
(5-year Swap Rate + 5.72%),
8.00%, 08/10/2025 ^(a),(b),(d)		861,000		836,548
Nordea Bank Abp
(5-year Treasury Constant Maturity Rate + 4.11%),
6.63%, 03/26/2026 ^{(a),(b),(c),(d)}		861,000		803,823
PNC Financial Services Group, Inc.
(5-year Treasury Constant Maturity Rate + 3.00%),
6.00%, 05/15/2027 ^(a),(b)		400,000		350,753
(5-year Treasury Constant Maturity Rate + 3.24%),
6.20%, 09/15/2027 ^(a),(b)		100,000		91,901
Societe Generale SA
(5-year Swap rate + 4.98%),
7.88%, 12/18/2023 ^(a),(b),(d)		824,000		817,199
Toronto-Dominion Bank
(5-year Treasury Constant Maturity Rate + 4.08%),
8.13%, 10/31/2082 ^(b)		414,000		411,870
Truist Financial Corp.
(5-year Treasury Constant Maturity Rate + 3.00%),
4.80%, 09/01/2024 ^(a),(b)		400,000		342,891
(5-year Treasury Constant Maturity Rate + 4.61%),
4.95%, 09/01/2025 ^(a),(b)		575,000		528,760
U.S. Bancorp
(5-year Treasury Constant Maturity Rate + 2.54%),
3.70%, 01/15/2027 ^(a),(b)		209,000		153,372
UBS Group AG
(5-year Swap rate + 4.34%),
7.00%, 01/31/2024 ^(a),(b),(d)		861,000		848,411
Wells Fargo & Co.
(5-year Treasury Constant Maturity Rate + 3.45%),
3.90%, 03/15/2026 ^(a),(b)		328,000		286,458

See accompanying notes.


	Schedule of Investments
	Principal Spectrum Tax-Advantaged Dividend Active ETF
	September 30, 2023 (unaudited)

			Principal
BONDS (continued)			Amount		Value

Banks (continued)
Wells Fargo & Co. (continued)
	(5-year Treasury Constant Maturity Rate + 3.61%),
	7.63%, 09/15/2028 ^(a),(b)	$	200,000	$	201,633
				$	14,033,821

Diversified Financial Services — 11.80%
American Express Co.
	(5-year Treasury Constant Maturity Rate + 2.85%),
	3.55%, 09/15/2026 ^(a),(b)		700,000		555,792
Capital One Financial Corp.
	(5-year Treasury Constant Maturity Rate + 3.16%),
	3.95%, 09/01/2026 ^(a),(b)		209,000		156,874
Charles Schwab Corp.
	(5-year Treasury Constant Maturity Rate + 3.17%),
	4.00%, 06/01/2026 ^(a),(b)		328,000		273,948
	(5-year Treasury Constant Maturity Rate + 4.97%),
	5.38%, 06/01/2025 ^(a),(b)		375,000		360,273
Discover Financial Services
	(5-year Treasury Constant Maturity Rate + 5.78%),
	6.13%, 06/23/2025 ^(a),(b)		575,000		552,670
Voya Financial, Inc.
	(5-year Treasury Constant Maturity Rate + 3.36%),
	7.75%, 09/15/2028 ^(a),(b)		460,000		463,244
				$	2,362,801

Electric — 4.90%
Dominion Energy, Inc.
	(5-year Treasury Constant Maturity Rate + 2.99%),
	4.65%, 12/15/2024 ^(a),(b)		460,000		421,066
Duke Energy Corp.
	(5-year Treasury Constant Maturity Rate + 3.39%),
	4.88%, 09/16/2024 ^(a),(b)		575,000		559,641
				$	980,707

Insurance — 1.02%
MetLife, Inc.
	(5-year Treasury Constant Maturity Rate + 3.58%),
	3.85%, 09/15/2025 ^(a),(b)		220,000		203,519
TOTAL BONDS				$	17,580,848
INVESTMENT COMPANIES — 0.93%			Shares Held		Value

Money Market Fund — 0.93%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(e)			187,272	$	187,272
TOTAL INVESTMENT COMPANIES				$	187,272
Total Investments				$	19,815,585
Other Assets and Liabilities — 1.03%					206,103

Total Net Assets — 100.00%				$	20,021,688

^(a)	Perpetual security. Perpetual securities pay an indefinite stream of interest, but they may be called by the issuer at an earlier
	date. Date shown, if any, reflects the next call date or final legal maturity date. Rate shown is as of period end.
^(b)	Rate shown is as of period end. The rate may be a variable or floating rate or a fixed rate which may convert to a variable or
	floating rate in the future.




See accompanying notes.		58

Schedule of Investments

Principal Spectrum Tax-Advantaged Dividend Active ETF

September 30, 2023 (unaudited)

^(c)	Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these securities totaled $993,676 or 4.96% of net assets.
^(d)	Security is a contingent convertible security, ("CoCo"). CoCo's are hybrid debt securities that may convert to equity or have their principal written down upon occurrence of certain "triggers". At the end of the period, the value of these securities totaled $6,744,338 or 33.69% of net assets.
^(e)	1-day yield shown as of period end.


Portfolio Summary

Sector	Percent
Financial	90.52	%
Utilities	4.90	%
Communications	2.62	%
Money Market Fund	0.93	%
Other Assets and Liabilities	1.03	%
TOTAL NET ASSETS	100.00	%

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.47%	Shares Held		Value

Advertising — 0.31%
Interpublic Group of Cos., Inc.	326	$	9,343
Omnicom Group, Inc.	138		10,278
		$	19,621

Aerospace & Defense — 1.40%
Boeing Co. ^(a)	43		8,242
General Dynamics Corp.	57		12,595
Howmet Aerospace, Inc.	111		5,134
L3Harris Technologies, Inc.	8		1,393
Lockheed Martin Corp.	59		24,129
Northrop Grumman Corp.	45		19,808
RTX Corp.	140		10,076
TransDigm Group, Inc. ^(a)	9		7,588
		$	88,965

Agriculture — 0.61%
Altria Group, Inc.	206		8,662
Archer-Daniels-Midland Co.	151		11,388
Bunge Ltd.	42		4,547
Philip Morris International, Inc.	151		13,980
		$	38,577

Airlines — 0.32%
American Airlines Group, Inc. ^(a)	232		2,972
Delta Air Lines, Inc.	258		9,546
United Airlines Holdings, Inc. ^(a)	182		7,698
		$	20,216

Apparel — 0.32%
NIKE, Inc., Class B	91		8,702
Ralph Lauren Corp.	57		6,617
Tapestry, Inc.	176		5,060
		$	20,379

Auto Manufacturers — 2.48%
Cummins, Inc.	65		14,850
General Motors Co.	171		5,638
PACCAR, Inc.	221		18,789
Tesla, Inc. ^(a)	473		118,354
		$	157,631

Auto Parts & Equipment — 0.21%
Aptiv PLC ^(a)	38		3,746
BorgWarner, Inc.	232		9,366
		$	13,112

Banks — 3.50%
Bank of America Corp.	489		13,389
Bank of New York Mellon Corp.	218		9,298
Citigroup, Inc.	187		7,691
Citizens Financial Group, Inc.	131		3,511
Comerica, Inc.	88		3,656
Fifth Third Bancorp	165		4,180
Goldman Sachs Group, Inc.	63		20,385
Huntington Bancshares, Inc.	997		10,369
JPMorgan Chase & Co.	514		74,540
KeyCorp	329		3,540

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Banks (continued)
M&T Bank Corp.	38	$	4,805
Morgan Stanley	231		18,866
Northern Trust Corp.	51		3,544
PNC Financial Services Group, Inc.	48		5,893
Regions Financial Corp.	236		4,059
State Street Corp.	120		8,035
Truist Financial Corp.	172		4,921
U.S. Bancorp	169		5,587
Wells Fargo & Co.	292		11,931
Zions Bancorp NA	126		4,396
		$	222,596

Beverages — 1.55%
Brown-Forman Corp., Class B	62		3,577
Coca-Cola Co.	573		32,076
Constellation Brands, Inc., Class A	26		6,534
Keurig Dr Pepper, Inc.	38		1,200
Molson Coors Beverage Co., Class B	157		9,984
Monster Beverage Corp. ^(a)	204		10,802
PepsiCo, Inc.	203		34,396
		$	98,569

Biotechnology — 1.42%
Amgen, Inc.	91		24,457
Biogen, Inc. ^(a)	37		9,510
Corteva, Inc.	114		5,832
Gilead Sciences, Inc.	240		17,986
Incyte Corp. ^(a)	64		3,697
Moderna, Inc. ^(a)	39		4,028
Regeneron Pharmaceuticals, Inc. ^(a)	9		7,407
Vertex Pharmaceuticals, Inc. ^(a)	50		17,387
		$	90,304

Building Materials — 0.79%
Carrier Global Corp.	319		17,609
Johnson Controls International PLC	82		4,363
Martin Marietta Materials, Inc.	10		4,105
Masco Corp.	148		7,911
Trane Technologies PLC	50		10,145
Vulcan Materials Co.	31		6,263
		$	50,396

Chemicals — 1.74%
Air Products & Chemicals, Inc.	49		13,887
Albemarle Corp.	56		9,522
Celanese Corp.	38		4,770
CF Industries Holdings, Inc.	102		8,745
Dow, Inc.	130		6,703
DuPont de Nemours, Inc.	84		6,266
Eastman Chemical Co.	48		3,683
FMC Corp.	63		4,219
Linde PLC	77		28,671
LyondellBasell Industries NV, Class A	109		10,322
Mosaic Co.	97		3,453
PPG Industries, Inc.	33		4,283
Sherwin-Williams Co.	24		6,121
		$	110,645

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Commercial Services — 1.95%
Automatic Data Processing, Inc.	79	$	19,006
Cintas Corp.	24		11,544
CoStar Group, Inc. ^(a)	116		8,919
FleetCor Technologies, Inc. ^(a)	36		9,192
Gartner, Inc. ^(a)	28		9,621
MarketAxess Holdings, Inc.	17		3,632
PayPal Holdings, Inc. ^(a)	88		5,145
Quanta Services, Inc.	55		10,289
Robert Half, Inc.	86		6,302
Rollins, Inc.	180		6,719
S&P Global, Inc.	33		12,059
United Rentals, Inc.	33		14,671
Verisk Analytics, Inc.	29		6,851
		$	123,950

Computers — 8.54%
Accenture PLC, Class A	88		27,026
Apple, Inc.	2,627		449,769
Cognizant Technology Solutions Corp., Class A	150		10,161
DXC Technology Co. ^(a)	153		3,187
EPAM Systems, Inc. ^(a)	24		6,136
Fortinet, Inc. ^(a)	71		4,166
Hewlett Packard Enterprise Co.	379		6,583
HP, Inc.	166		4,266
International Business Machines Corp.	92		12,908
Leidos Holdings, Inc.	87		8,018
NetApp, Inc.	81		6,146
Seagate Technology Holdings PLC	63		4,155
		$	542,521

Cosmetics & Personal Care — 0.79%
Colgate-Palmolive Co.	182		12,942
Procter & Gamble Co.	256		37,340
		$	50,282

Distribution/Wholesale — 0.77%
Copart, Inc. ^(a)	266		11,462
Fastenal Co.	99		5,409
LKQ Corp.	215		10,645
Pool Corp.	21		7,478
WW Grainger, Inc.	20		13,837
		$	48,831

Diversified Financial Services — 3.57%
American Express Co.	100		14,919
Ameriprise Financial, Inc.	32		10,550
BlackRock, Inc.	24		15,516
Capital One Financial Corp.	60		5,823
Cboe Global Markets, Inc.	35		5,467
Charles Schwab Corp.	122		6,698
CME Group, Inc.	43		8,610
Discover Financial Services	48		4,158
Franklin Resources, Inc.	261		6,415
Intercontinental Exchange, Inc.	71		7,811
Invesco Ltd.	245		3,557
Mastercard, Inc., Class A	127		50,281
Nasdaq, Inc.	161		7,823
Raymond James Financial, Inc.	84		8,436

See accompanying notes.


Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Diversified Financial Services (continued)
Synchrony Financial	261	$	7,979
T Rowe Price Group, Inc.	43		4,509
Visa, Inc., Class A	252		57,963
		$	226,515

Electric — 1.64%
AES Corp.	154		2,341
Alliant Energy Corp.	77		3,731
Ameren Corp.	55		4,116
American Electric Power Co., Inc.	75		5,641
CenterPoint Energy, Inc.	39		1,047
CMS Energy Corp.	72		3,824
Consolidated Edison, Inc.	103		8,809
Constellation Energy Corp.	53		5,781
Dominion Energy, Inc.	30		1,340
DTE Energy Co.	44		4,368
Duke Energy Corp.	87		7,679
Edison International	79		5,000
Entergy Corp.	12		1,110
Evergy, Inc.	18		913
Eversource Energy	65		3,780
Exelon Corp.	38		1,436
FirstEnergy Corp.	133		4,546
NextEra Energy, Inc.	46		2,635
NRG Energy, Inc.	118		4,545
PG&E Corp. ^(a)	336		5,420
Pinnacle West Capital Corp.	54		3,979
PPL Corp.	186		4,382
Public Service Enterprise Group, Inc.	23		1,309
Sempra	24		1,633
Southern Co.	31		2,006
WEC Energy Group, Inc.	100		8,055
Xcel Energy, Inc.	86		4,921
		$	104,347

Electrical Components & Equipment — 0.28%
AMETEK, Inc.	68		10,048
Emerson Electric Co.	78		7,532
		$	17,580

Electronics — 1.21%
Agilent Technologies, Inc.	68		7,604
Allegion PLC	95		9,899
Amphenol Corp., Class A	146		12,263
Fortive Corp.	79		5,859
Garmin Ltd.	41		4,313
Honeywell International, Inc.	68		12,562
Keysight Technologies, Inc. ^(a)	49		6,483
Mettler-Toledo International, Inc. ^(a)	6		6,648
TE Connectivity Ltd.	92		11,365
		$	76,996

Energy — Alternate Sources — 0.08%
Enphase Energy, Inc. ^(a)	17		2,042
First Solar, Inc. ^(a)	18		2,909
		$	4,951

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Engineering & Construction — 0.15%
Jacobs Solutions, Inc.	71	$	9,691

Entertainment — 0.08%
Live Nation Entertainment, Inc. ^(a)	58		4,816

Environmental Control — 0.33%
Pentair PLC	133		8,612
Republic Services, Inc.	38		5,415
Waste Management, Inc.	46		7,012
		$	21,039

Food — 1.53%
Campbell Soup Co.	151		6,203
Conagra Brands, Inc.	129		3,537
General Mills, Inc.	212		13,566
Hershey Co.	42		8,404
Hormel Foods Corp.	105		3,993
J M Smucker Co.	31		3,810
Kellogg Co.	180		10,712
Kraft Heinz Co.	149		5,012
Kroger Co.	211		9,442
Lamb Weston Holdings, Inc.	74		6,842
McCormick & Co., Inc.	16		1,210
Mondelez International, Inc., Class A	148		10,271
Sysco Corp.	144		9,511
Tyson Foods, Inc., Class A	93		4,696
		$	97,209

Forest Products & Paper — 0.06%
International Paper Co.	114		4,044

Gas — 0.17%
Atmos Energy Corp.	69		7,309
NiSource, Inc.	144		3,554
		$	10,863

Hand/Machine Tools — 0.20%
Snap-on, Inc.	49		12,498

Healthcare — Products — 1.85%
Abbott Laboratories	156		15,108
Bio-Techne Corp.	40		2,723
Boston Scientific Corp. ^(a)	174		9,187
Danaher Corp.	44		10,916
Edwards Lifesciences Corp. ^(a)	60		4,157
GE HealthCare Technologies, Inc.	116		7,893
Hologic, Inc. ^(a)	115		7,981
IDEXX Laboratories, Inc. ^(a)	19		8,308
Insulet Corp. ^(a)	12		1,914
Medtronic PLC	33		2,586
ResMed, Inc.	26		3,845
Stryker Corp.	53		14,483
Thermo Fisher Scientific, Inc.	33		16,704
Waters Corp. ^(a)	11		3,016
West Pharmaceutical Services, Inc.	11		4,127
Zimmer Biomet Holdings, Inc.	41		4,601
		$	117,549

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Healthcare — Services — 3.01%
Catalent, Inc. ^(a)	43	$	1,958
Centene Corp. ^(a)	103		7,095
Charles River Laboratories International, Inc. ^(a)	34		6,663
DaVita, Inc. ^(a)	47		4,443
Elevance Health, Inc.	43		18,723
HCA Healthcare, Inc.	53		13,037
Humana, Inc.	40		19,461
IQVIA Holdings, Inc. ^(a)	48		9,444
Laboratory Corp. of America Holdings	26		5,227
Molina Healthcare, Inc. ^(a)	31		10,165
Quest Diagnostics, Inc.	38		4,631
UnitedHealth Group, Inc.	165		83,191
Universal Health Services, Inc., Class B	55		6,915
		$	190,953

Home Builders — 0.84%
DR Horton, Inc.	134		14,401
Lennar Corp., Class A	119		13,355
NVR, Inc. ^(a)	2		11,927
PulteGroup, Inc.	181		13,403
		$	53,086

Home Furnishings — 0.06%
Whirlpool Corp.	29		3,877

Household Products/Wares — 0.51%
Avery Dennison Corp.	70		12,787
Church & Dwight Co., Inc.	53		4,856
Clorox Co.	31		4,063
Kimberly-Clark Corp.	87		10,514
		$	32,220

Insurance — 4.10%
Aflac, Inc.	178		13,662
Allstate Corp.	46		5,125
American International Group, Inc.	110		6,666
Aon PLC, Class A	44		14,266
Arch Capital Group Ltd. ^(a)	129		10,283
Arthur J Gallagher & Co.	58		13,220
Assurant, Inc.	35		5,025
Berkshire Hathaway, Inc., Class B ^(a)	189		66,207
Brown & Brown, Inc.	143		9,987
Chubb Ltd.	52		10,825
Everest Group Ltd.	22		8,177
Globe Life, Inc.	102		11,090
Hartford Financial Services Group, Inc.	143		10,140
Lincoln National Corp.	167		4,123
Loews Corp.	90		5,698
Marsh & McLennan Cos., Inc.	54		10,276
MetLife, Inc.	123		7,738
Progressive Corp.	121		16,855
Prudential Financial, Inc.	63		5,978
Travelers Cos., Inc.	71		11,595
W R Berkley Corp.	132		8,381
Willis Towers Watson PLC	24		5,015
		$	260,332

See accompanying notes.


Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Internet — 10.29%
Alphabet, Inc., Class A ^(a)	1,054	$	137,927
Alphabet, Inc., Class C ^(a)	912		120,247
Amazon.com, Inc. ^(a)	1,576		200,341
Booking Holdings, Inc. ^(a)	6		18,504
CDW Corp.	70		14,123
Expedia Group, Inc. ^(a)	48		4,947
F5, Inc. ^(a)	26		4,190
Gen Digital, Inc.	231		4,084
Meta Platforms, Inc., Class A ^(a)	393		117,983
Netflix, Inc. ^(a)	62		23,411
VeriSign, Inc. ^(a)	40		8,101
		$	653,858

Iron & Steel — 0.41%
Nucor Corp.	97		15,166
Steel Dynamics, Inc.	102		10,936
		$	26,102

Leisure Time — 0.08%
Royal Caribbean Cruises Ltd. ^(a)	55		5,068

Lodging — 0.60%
Hilton Worldwide Holdings, Inc.	44		6,608
Las Vegas Sands Corp.	68		3,117
Marriott International, Inc., Class A	98		19,263
MGM Resorts International ^(a)	179		6,580
Wynn Resorts Ltd.	30		2,772
		$	38,340

Machinery — Construction & Mining — 0.35%
Caterpillar, Inc.	82		22,386

Machinery — Diversified — 1.19%
Deere & Co.	64		24,152
Dover Corp.	59		8,231
IDEX Corp.	36		7,489
Ingersoll Rand, Inc.	70		4,461
Nordson Corp.	14		3,124
Otis Worldwide Corp.	74		5,943
Rockwell Automation, Inc.	30		8,576
Westinghouse Air Brake Technologies Corp.	95		10,096
Xylem, Inc.	36		3,277
		$	75,349

Media — 1.06%
Charter Communications, Inc., Class A ^(a)	27		11,875
Comcast Corp., Class A	410		18,179
DISH Network Corp., Class A ^(a)	390		2,285
FactSet Research Systems, Inc.	19		8,308
Fox Corp., Class A	230		7,176
Fox Corp., Class B	146		4,217
News Corp., Class A	224		4,494
News Corp., Class B	205		4,278
Paramount Global, Class B	189		2,438
Warner Bros Discovery, Inc. ^(a)	354		3,845
		$	67,095

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Mining — 0.10%
Freeport-McMoRan, Inc.	163	$	6,078

Miscellaneous Manufacturers — 1.29%
3M Co.	128		11,984
A O Smith Corp.	48		3,174
Eaton Corp. PLC	48		10,238
General Electric Co.	180		19,899
Illinois Tool Works, Inc.	58		13,358
Parker-Hannifin Corp.	16		6,232
Teledyne Technologies, Inc. ^(a)	19		7,763
Textron, Inc.	123		9,611
		$	82,259

Oil & Gas — 4.60%
APA Corp.	114		4,685
Chevron Corp.	270		45,527
ConocoPhillips	191		22,882
Coterra Energy, Inc.	319		8,629
Devon Energy Corp.	106		5,056
Diamondback Energy, Inc.	65		10,067
EOG Resources, Inc.	114		14,451
EQT Corp.	127		5,154
Exxon Mobil Corp.	722		84,893
Hess Corp.	37		5,661
Marathon Oil Corp.	316		8,453
Marathon Petroleum Corp.	137		20,734
Occidental Petroleum Corp.	96		6,228
Phillips 66	161		19,344
Pioneer Natural Resources Co.	55		12,625
Valero Energy Corp.	124		17,572
		$	291,961

Oil & Gas Services — 0.23%
Halliburton Co.	160		6,480
Schlumberger NV	137		7,987
		$	14,467

Packaging & Containers — 0.45%
Amcor PLC	1,095		10,030
Packaging Corp. of America	60		9,213
Sealed Air Corp.	147		4,831
Westrock Co.	128		4,582
		$	28,656

Pharmaceuticals — 6.39%
AbbVie, Inc.	369		55,003
Becton Dickinson & Co.	58		14,995
Bristol-Myers Squibb Co.	356		20,662
Cardinal Health, Inc.	130		11,287
Cencora, Inc.	87		15,657
Cigna Group	64		18,308
CVS Health Corp.	147		10,264
Dexcom, Inc. ^(a)	83		7,744
Eli Lilly & Co.	138		74,124
Henry Schein, Inc. ^(a)	62		4,604
Johnson & Johnson	308		47,971
McKesson Corp.	51		22,177
Merck & Co., Inc.	533		54,872

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Pharmaceuticals (continued)
Organon & Co.	163	$	2,830
Pfizer, Inc.	848		28,128
Viatris, Inc.	1,081		10,659
Zoetis, Inc.	39		6,785
		$	406,070

Pipelines — 0.50%
Kinder Morgan, Inc.	649		10,761
ONEOK, Inc.	153		9,705
Targa Resources Corp.	60		5,143
Williams Cos., Inc.	193		6,502
		$	32,111

Real Estate — 0.07%
CBRE Group, Inc., Class A ^(a)	65		4,801

REITs — 1.49%
AvalonBay Communities, Inc.	30		5,152
Boston Properties, Inc.	74		4,402
Camden Property Trust	37		3,500
Crown Castle, Inc.	41		3,773
Equinix, Inc.	17		12,346
Equity Residential	21		1,233
Extra Space Storage, Inc.	22		2,675
Federal Realty Investment Trust	10		906
Host Hotels & Resorts, Inc.	259		4,162
Iron Mountain, Inc.	131		7,788
Mid-America Apartment Communities, Inc.	28		3,602
Prologis, Inc.	69		7,743
Public Storage	22		5,798
Realty Income Corp.	102		5,094
Regency Centers Corp.	64		3,804
SBA Communications Corp.	14		2,802
Simon Property Group, Inc.	92		9,939
VICI Properties, Inc.	184		5,354
Weyerhaeuser Co.	156		4,783
		$	94,856

Retail — 4.63%
Advance Auto Parts, Inc.	34		1,902
AutoZone, Inc. ^(a)	7		17,780
Bath & Body Works, Inc.	100		3,380
Best Buy Co., Inc.	56		3,890
CarMax, Inc. ^(a)	64		4,527
Chipotle Mexican Grill, Inc. ^(a)	6		10,991
Costco Wholesale Corp.	37		20,903
Darden Restaurants, Inc.	58		8,307
Dollar General Corp.	57		6,031
Dollar Tree, Inc. ^(a)	63		6,706
Genuine Parts Co.	83		11,983
Home Depot, Inc.	156		47,137
Lowe's Cos., Inc.	50		10,392
McDonald's Corp.	65		17,124
O'Reilly Automotive, Inc. ^(a)	22		19,995
Ross Stores, Inc.	58		6,551
Starbucks Corp.	115		10,496
TJX Cos., Inc.	127		11,288
Tractor Supply Co.	39		7,919

See accompanying notes.


	Schedule of Investments
Principal U.S. Large-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Retail (continued)
Ulta Beauty, Inc. ^(a)	27	$	10,785
Walmart, Inc.	314		50,218
Yum! Brands, Inc.	46		5,747
		$	294,052

Semiconductors — 6.69%
Analog Devices, Inc.	79		13,832
Applied Materials, Inc.	136		18,829
Broadcom, Inc.	54		44,851
KLA Corp.	44		20,181
Lam Research Corp.	38		23,817
Microchip Technology, Inc.	190		14,830
Micron Technology, Inc.	112		7,619
Monolithic Power Systems, Inc.	15		6,930
NVIDIA Corp.	433		188,351
NXP Semiconductors NV	87		17,393
ON Semiconductor Corp. ^(a)	176		16,359
Qorvo, Inc. ^(a)	39		3,723
QUALCOMM, Inc.	165		18,325
Skyworks Solutions, Inc.	66		6,507
Texas Instruments, Inc.	146		23,216
		$	424,763

Shipbuilding — 0.12%
Huntington Ingalls Industries, Inc.	39		7,979

Software — 9.02%
Activision Blizzard, Inc.	92		8,614
Adobe, Inc. ^(a)	30		15,297
Akamai Technologies, Inc. ^(a)	52		5,540
ANSYS, Inc. ^(a)	25		7,439
Autodesk, Inc. ^(a)	22		4,552
Broadridge Financial Solutions, Inc.	31		5,551
Cadence Design Systems, Inc. ^(a)	55		12,886
Ceridian HCM Holding, Inc. ^(a)	47		3,189
Electronic Arts, Inc.	43		5,177
Fair Isaac Corp. ^(a)	5		4,343
Fiserv, Inc. ^(a)	112		12,652
Intuit, Inc.	20		10,219
Jack Henry & Associates, Inc.	20		3,023
Microsoft Corp.	1,315		415,211
MSCI, Inc.	18		9,235
Oracle Corp.	147		15,570
Paychex, Inc.	51		5,882
Paycom Software, Inc.	11		2,852
PTC, Inc. ^(a)	35		4,959
Roper Technologies, Inc.	15		7,264
Synopsys, Inc. ^(a)	29		13,310
		$	572,765

Telecommunications — 1.80%
Arista Networks, Inc. ^(a)	56		10,300
AT&T, Inc.	690		10,364
Cisco Systems, Inc.	912		49,029
Corning, Inc.	38		1,158
Juniper Networks, Inc.	30		834
Motorola Solutions, Inc.	41		11,162
T-Mobile U.S., Inc. ^(a)	67		9,383

See accompanying notes.


		Schedule of Investments
	Principal U.S. Large-Cap Adaptive Multi-Factor ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held			Value

Telecommunications (continued)
Verizon Communications, Inc.		680		$	22,039
				$	114,269

Transportation — 1.67%
CH Robinson Worldwide, Inc.		82			7,062
CSX Corp.		485			14,914
Expeditors International of Washington, Inc.		103			11,807
FedEx Corp.		54			14,306
JB Hunt Transport Services, Inc.		42			7,918
Norfolk Southern Corp.		59			11,619
Old Dominion Freight Line, Inc.		24			9,819
Union Pacific Corp.		45			9,163
United Parcel Service, Inc., Class B		125			19,484
				$	106,092

Water — 0.07%
American Water Works Co., Inc.		35			4,334
TOTAL COMMON STOCKS				$	6,318,872
INVESTMENT COMPANIES — 0.47%		Shares Held			Value

Money Market Fund — 0.47%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)		29,607		$	29,607
TOTAL INVESTMENT COMPANIES				$	29,607
Total Investments				$	6,348,479
Other Assets and Liabilities — 0.06%					4,077
Total Net Assets — 100.00%				$	6,352,556

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Technology		24.24	%
Consumer, Non-cyclical		19.61	%
Communications		13.46	%
Financial		12.74	%
Consumer, Cyclical		10.38	%
Industrial		9.44	%
Energy		5.41	%
Basic Materials		2.31	%
Utilities		1.88	%
Money Market Fund		0.47	%
Other Assets and Liabilities		0.06	%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		70


	Schedule of Investments
	Principal U.S. Mega-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.55%		Shares Held		Value
Auto Manufacturers — 3.15%
Tesla, Inc. ^(a)		184,363	$	46,131,310
Banks — 5.18%
Bank of America Corp.		1,017,774		27,866,652
JPMorgan Chase & Co.		216,354		31,375,657
Wells Fargo & Co.		405,090		16,551,978
			$	75,794,287

Beverages — 2.86%
Coca-Cola Co.		474,647		26,570,739
PepsiCo, Inc.		90,104		15,267,222
			$	41,837,961

Chemicals — 1.16%
Linde PLC		45,624		16,988,096
Computers — 10.28%
Accenture PLC, Class A		159,940		49,119,173
Apple, Inc.		591,704		101,305,642
			$	150,424,815

Diversified Financial Services — 6.15%
Mastercard, Inc., Class A		117,775		46,628,300
Visa, Inc., Class A		188,828		43,432,329
			$	90,060,629

Electric — 0.83%
NextEra Energy, Inc.		211,501		12,116,892
Healthcare — Products — 6.61%
Abbott Laboratories		272,274		26,369,737
Danaher Corp.		174,825		43,374,083
Thermo Fisher Scientific, Inc.		53,173		26,914,577
			$	96,658,397

Healthcare — Services — 3.15%
UnitedHealth Group, Inc.		91,355		46,060,277
Household Products — 1.94%
Procter & Gamble Co.		194,801		28,413,674
Insurance — 1.23%
Berkshire Hathaway, Inc., Class B ^(a)		51,503		18,041,501
Internet — 9.16%
Alphabet, Inc., Class A ^(a)		419,291		54,868,420
Amazon.com, Inc. ^(a)		284,376		36,149,877
Meta Platforms, Inc., Class A ^(a)		143,216		42,994,876
			$	134,013,173

Media — 2.27%
Comcast Corp., Class A		442,658		19,627,456
Walt Disney Co. ^(a)		167,788		13,599,217
			$	33,226,673

Oil & Gas — 5.13%
Chevron Corp.		179,737		30,307,253
Exxon Mobil Corp.		380,982		44,795,864
			$	75,103,117

See accompanying notes.


		Schedule of Investments
		Principal U.S. Mega-Cap ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)				Shares Held		Value
Pharmaceuticals — 9.84%
AbbVie, Inc.				187,131	$	27,893,747
Eli Lilly & Co.				43,357		23,288,346
Johnson & Johnson				187,392		29,186,304
Merck & Co., Inc.				263,533		27,130,722
Pfizer, Inc.				1,099,155		36,458,971
					$	143,958,090

Retail — 7.70%
Costco Wholesale Corp.				87,290		49,315,358
Home Depot, Inc.				101,337		30,619,988
McDonald's Corp.				57,207		15,070,612
Walmart, Inc.				110,099		17,608,133
					$	112,614,091

Semiconductors — 7.94%
Broadcom, Inc.				48,066		39,922,658
NVIDIA Corp.				112,430		48,905,926
Texas Instruments, Inc.				171,747		27,309,490
					$	116,138,074

Software — 12.59%
Adobe, Inc. ^(a)				117,020		59,668,498
Microsoft Corp.				296,148		93,508,731
Salesforce, Inc. ^(a)				152,787		30,982,148
					$	184,159,377

Telecommunications — 2.38%
Cisco Systems, Inc.				648,262		34,850,565
TOTAL COMMON STOCKS					$	1,456,590,999
INVESTMENT COMPANIES — 0.41%				Shares Held		Value
Money Market Fund — 0.41%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)				6,076,360	$	6,076,360
TOTAL INVESTMENT COMPANIES					$	6,076,360
Total Investments					$	1,462,667,359
Other Assets and Liabilities — 0.04%						540,618
Total Net Assets — 100.00%					$	1,463,207,977

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Technology		30.80	%
Consumer, Non-cyclical		24.40	%
Communications		13.81	%
Financial		12.57	%
Consumer, Cyclical		10.85	%
Energy		5.13	%
Basic Materials		1.16	%
Utilities		0.83	%
Money Market Fund		0.41	%
Other Assets and Liabilities		0.04	%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		72


Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS — 99.49%	Shares Held		Value

Aerospace & Defense — 0.97%
AAR Corp. ^(a)	273	$	16,252
Barnes Group, Inc.	229		7,779
Moog, Inc., Class A	199		22,479
National Presto Industries, Inc.	69		5,000
Triumph Group, Inc. ^(a)	464		3,554
		$	55,064

Agriculture — 0.58%
Andersons, Inc.	274		14,114
Fresh Del Monte Produce, Inc.	387		10,000
Universal Corp.	35		1,652
Vector Group Ltd.	669		7,118
		$	32,884

Airlines — 0.21%
SkyWest, Inc. ^(a)	287		12,037

Apparel — 1.24%
Kontoor Brands, Inc.	482		21,165
Oxford Industries, Inc.	180		17,303
Steven Madden Ltd.	762		24,209
Urban Outfitters, Inc. ^(a)	226		7,388
		$	70,065

Auto Manufacturers — 0.25%
Wabash National Corp.	674		14,235

Auto Parts & Equipment — 1.18%
American Axle & Manufacturing Holdings, Inc. ^(a)	1,318		9,569
Dorman Products, Inc. ^(a)	116		8,788
Methode Electronics, Inc.	488		11,151
Standard Motor Products, Inc.	405		13,616
Titan International, Inc. ^(a)	795		10,677
XPEL, Inc. ^(a)	169		13,031
		$	66,832

Banks — 9.53%
Ameris Bancorp	631		24,224
Atlantic Union Bankshares Corp.	558		16,059
BancFirst Corp.	88		7,632
Bancorp, Inc. ^(a)	201		6,934
BankUnited, Inc.	301		6,833
Banner Corp.	410		17,376
Central Pacific Financial Corp.	520		8,674
City Holding Co.	137		12,378
Community Bank System, Inc.	212		8,949
Customers Bancorp, Inc. ^(a)	473		16,295
CVB Financial Corp.	855		14,167
Dime Community Bancshares, Inc.	390		7,784
Eagle Bancorp, Inc.	348		7,465
FB Financial Corp.	386		10,947
First BanCorp	1,483		19,961
First BanCorp/Southern Pines NC	391		11,003
First Commonwealth Financial Corp.	1,055		12,882
First Financial Bancorp	729		14,288
First Hawaiian, Inc.	534		9,639
Hanmi Financial Corp.	519		8,423
Heritage Financial Corp.	707		11,531

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Banks (continued)
Hilltop Holdings, Inc.	470	$	13,329
HomeStreet, Inc.	230		1,792
Hope Bancorp, Inc.	1,231		10,894
Independent Bank Corp.	314		15,414
Independent Bank Group, Inc.	325		12,854
Lakeland Financial Corp.	122		5,790
National Bank Holdings Corp., Class A	231		6,875
NBT Bancorp, Inc.	573		18,158
OFG Bancorp	506		15,109
Park National Corp.	67		6,333
Pathward Financial, Inc.	116		5,346
Preferred Bank	191		11,890
Renasant Corp.	694		18,176
S&T Bancorp, Inc.	577		15,625
Seacoast Banking Corp. of Florida	269		5,907
ServisFirst Bancshares, Inc.	142		7,408
Simmons First National Corp., Class A	570		9,667
Southside Bancshares, Inc.	343		9,844
Stellar Bancorp, Inc.	254		5,415
Tompkins Financial Corp.	237		11,611
Triumph Financial, Inc. ^(a)	95		6,155
TrustCo Bank Corp.	316		8,624
Trustmark Corp.	583		12,669
United Community Banks, Inc.	780		19,820
Veritex Holdings, Inc.	525		9,424
Walker & Dunlop, Inc.	203		15,071
Westamerica BanCorp	148		6,401
		$	539,045

Beverages — 0.46%
MGP Ingredients, Inc.	142		14,978
National Beverage Corp. ^(a)	230		10,815
		$	25,793

Biotechnology — 1.09%
ANI Pharmaceuticals, Inc. ^(a)	108		6,270
Certara, Inc. ^(a)	322		4,682
Dynavax Technologies Corp. ^(a)	1,115		16,468
Innoviva, Inc. ^(a)	913		11,860
iTeos Therapeutics, Inc. ^(a)	307		3,362
Ligand Pharmaceuticals, Inc. ^(a)	72		4,314
NeoGenomics, Inc. ^(a)	412		5,068
Vir Biotechnology, Inc. ^(a)	576		5,397
Xencor, Inc. ^(a)	218		4,393
		$	61,814

Building Materials — 3.06%
AAON, Inc.	336		19,108
American Woodmark Corp. ^(a)	285		21,549
Apogee Enterprises, Inc.	282		13,277
Boise Cascade Co.	298		30,706
Gibraltar Industries, Inc. ^(a)	421		28,422
Griffon Corp.	188		7,458
Masterbrand, Inc. ^(a)	1,425		17,314
PGT Innovations, Inc. ^(a)	771		21,395
SPX Technologies, Inc. ^(a)	173		14,082
		$	173,311

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Chemicals — 2.48%
AdvanSix, Inc.	322	$	10,008
American Vanguard Corp.	640		6,995
Balchem Corp.	114		14,141
Hawkins, Inc.	136		8,004
HB Fuller Co.	190		13,036
Innospec, Inc.	176		17,987
Koppers Holdings, Inc.	322		12,735
Livent Corp. ^(a)	467		8,597
Mativ Holdings, Inc.	523		7,458
Minerals Technologies, Inc.	163		8,926
Quaker Chemical Corp.	83		13,280
Rogers Corp. ^(a)	54		7,099
Stepan Co.	163		12,220
		$	140,486

Coal — 1.23%
CONSOL Energy, Inc.	361		37,872
SunCoke Energy, Inc.	1,245		12,637
Warrior Met Coal, Inc.	376		19,206
		$	69,715

Commercial Services — 5.73%
Aaron's Co., Inc.	445		4,659
ABM Industries, Inc.	662		26,487
Adtalem Global Education, Inc. ^(a)	393		16,840
Alarm.com Holdings, Inc. ^(a)	207		12,656
AMN Healthcare Services, Inc. ^(a)	242		20,614
CoreCivic, Inc. ^(a)	1,204		13,545
CorVel Corp. ^(a)	43		8,456
Cross Country Healthcare, Inc. ^(a)	625		15,494
Deluxe Corp.	316		5,969
EVERTEC, Inc.	518		19,259
Forrester Research, Inc. ^(a)	106		3,063
GEO Group, Inc. ^(a)	1,973		16,139
Green Dot Corp., Class A ^(a)	563		7,843
Healthcare Services Group, Inc.	368		3,838
Heidrick & Struggles International, Inc.	288		7,206
Kelly Services, Inc., Class A	85		1,546
Korn Ferry	385		18,264
Matthews International Corp., Class A	191		7,432
Medifast, Inc.	109		8,159
Mister Car Wash, Inc. ^(a)	472		2,601
Monro, Inc.	292		8,109
Payoneer Global, Inc. ^(a)	865		5,294
Perdoceo Education Corp.	906		15,493
PROG Holdings, Inc. ^(a)	488		16,206
Resources Connection, Inc.	722		10,765
Strategic Education, Inc.	102		7,676
Stride, Inc. ^(a)	479		21,569
TrueBlue, Inc. ^(a)	347		5,090
Upbound Group, Inc.	483		14,224
		$	324,496

Computers — 0.94%
Corsair Gaming, Inc. ^(a)	250		3,632
Insight Enterprises, Inc. ^(a)	266		38,703
NetScout Systems, Inc. ^(a)	77		2,158
OneSpan, Inc. ^(a)	238		2,558

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Computers (continued)
TTEC Holdings, Inc.	244	$	6,398
		$	53,449

Cosmetics & Personal Care — 0.97%
Edgewell Personal Care Co.	224		8,279
elf Beauty, Inc. ^(a)	267		29,325
Inter Parfums, Inc.	127		17,061
		$	54,665

Distribution/Wholesale — 0.76%
G-III Apparel Group Ltd. ^(a)	330		8,224
Resideo Technologies, Inc. ^(a)	942		14,883
ScanSource, Inc. ^(a)	361		10,942
Veritiv Corp.	54		9,121
		$	43,170

Diversified Financial Services — 3.14%
Avantax, Inc. ^(a)	257		6,574
Bread Financial Holdings, Inc.	221		7,558
Brightsphere Investment Group, Inc.	462		8,958
Encore Capital Group, Inc. ^(a)	160		7,642
Enova International, Inc. ^(a)	274		13,939
EZCORP, Inc., Class A ^(a)	1,613		13,307
LendingTree, Inc. ^(a)	160		2,480
Mr Cooper Group, Inc. ^(a)	500		26,780
Piper Sandler Cos.	64		9,300
PRA Group, Inc. ^(a)	197		3,784
Radian Group, Inc.	1,478		37,113
StoneX Group, Inc. ^(a)	198		19,190
Virtus Investment Partners, Inc.	35		7,070
WisdomTree, Inc.	985		6,895
World Acceptance Corp. ^(a)	55		6,988
		$	177,578

Electric — 0.86%
Avista Corp.	280		9,064
Otter Tail Corp.	412		31,279
Unitil Corp.	192		8,200
		$	48,543

Electrical Components & Equipment — 0.83%
Encore Wire Corp.	160		29,193
Insteel Industries, Inc.	319		10,355
Powell Industries, Inc.	90		7,461
		$	47,009

Electronics — 3.65%
Advanced Energy Industries, Inc.	236		24,336
Badger Meter, Inc.	188		27,048
Benchmark Electronics, Inc.	692		16,788
Brady Corp., Class A	339		18,618
Comtech Telecommunications Corp.	299		2,616
CTS Corp.	298		12,439
ESCO Technologies, Inc.	191		19,948
Itron, Inc. ^(a)	142		8,602
OSI Systems, Inc. ^(a)	137		16,172
Plexus Corp. ^(a)	196		18,224

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value
Electronics (continued)
Sanmina Corp. ^(a)	551	$	29,908
TTM Technologies, Inc. ^(a)	907		11,682
		$	206,381

Energy — Alternate Sources — 0.33%
FutureFuel Corp.	1,007		7,220
REX American Resources Corp. ^(a)	280		11,402
		$	18,622

Engineering & Construction — 2.39%
Arcosa, Inc.	329		23,655
Comfort Systems USA, Inc.	301		51,294
Dycom Industries, Inc. ^(a)	88		7,832
Frontdoor, Inc. ^(a)	536		16,396
Granite Construction, Inc.	208		7,908
MYR Group, Inc. ^(a)	174		23,448
NV5 Global, Inc. ^(a)	51		4,908
		$	135,441

Entertainment — 0.29%
Golden Entertainment, Inc.	130		4,443
Monarch Casino & Resort, Inc.	85		5,279
Six Flags Entertainment Corp. ^(a)	292		6,865
		$	16,587

Food — 2.20%
Cal-Maine Foods, Inc.	392		18,981
Calavo Growers, Inc.	324		8,174
Chefs' Warehouse, Inc. ^(a)	197		4,172
Hostess Brands, Inc. ^(a)	878		29,246
J & J Snack Foods Corp.	65		10,637
John B Sanfilippo & Son, Inc.	119		11,757
Seneca Foods Corp., Class A ^(a)	102		5,491
Simply Good Foods Co. ^(a)	306		10,563
SpartanNash Co.	276		6,072
Tootsie Roll Industries, Inc.	228		6,808
TreeHouse Foods, Inc. ^(a)	208		9,065
United Natural Foods, Inc. ^(a)	268		3,790
		$	124,756

Forest Products & Paper — 0.48%
Mercer International, Inc.	934		8,014
Sylvamo Corp.	432		18,982
		$	26,996

Gas — 0.33%
Chesapeake Utilities Corp.	73		7,136
Northwest Natural Holding Co.	301		11,486
		$	18,622

Hand/Machine Tools — 0.69%
Enerpac Tool Group Corp.	294		7,770
Franklin Electric Co., Inc.	249		22,218
Kennametal, Inc.	353		8,783
		$	38,771

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Healthcare — Products — 1.30%
Avanos Medical, Inc. ^(a)	435	$	8,796
BioLife Solutions, Inc. ^(a)	202		2,790
Embecta Corp.	226		3,401
Glaukos Corp. ^(a)	50		3,763
Integer Holdings Corp. ^(a)	105		8,235
LeMaitre Vascular, Inc.	224		12,204
Merit Medical Systems, Inc. ^(a)	347		23,950
OraSure Technologies, Inc. ^(a)	651		3,860
Varex Imaging Corp. ^(a)	93		1,747
Zynex, Inc. ^(a)	598		4,784
		$	73,530

Healthcare — Services — 1.49%
Addus HomeCare Corp. ^(a)	135		11,501
Agiliti, Inc. ^(a)	248		1,609
Community Health Systems, Inc. ^(a)	1,013		2,938
Enhabit, Inc. ^(a)	661		7,436
Ensign Group, Inc.	181		16,820
Fulgent Genetics, Inc. ^(a)	151		4,038
Pediatrix Medical Group, Inc. ^(a)	405		5,148
RadNet, Inc. ^(a)	218		6,145
Select Medical Holdings Corp.	670		16,931
U.S. Physical Therapy, Inc.	131		12,017
		$	84,583

Home Builders — 4.55%
Cavco Industries, Inc. ^(a)	79		20,987
Century Communities, Inc.	210		14,024
Green Brick Partners, Inc. ^(a)	430		17,849
Installed Building Products, Inc.	220		27,476
LCI Industries	235		27,593
LGI Homes, Inc. ^(a)	128		12,735
M/I Homes, Inc. ^(a)	346		29,078
MDC Holdings, Inc.	452		18,636
Meritage Homes Corp.	321		39,287
Tri Pointe Homes, Inc. ^(a)	1,065		29,128
Winnebago Industries, Inc.	347		20,629
		$	257,422

Home Furnishings — 0.44%
Ethan Allen Interiors, Inc.	539		16,116
iRobot Corp. ^(a)	38		1,440
Sleep Number Corp. ^(a)	164		4,033
Xperi, Inc. ^(a)	364		3,589
		$	25,178

Household Products/Wares — 1.14%
Central Garden & Pet Co. ^(a)	228		10,064
Central Garden & Pet Co., Class A ^(a)	385		15,435
Quanex Building Products Corp.	662		18,648
WD-40 Co.	100		20,324
		$	64,471

Insurance — 2.85%
Ambac Financial Group, Inc. ^(a)	707		8,527
American Equity Investment Life Holding Co. ^(a)	449		24,084
AMERISAFE, Inc.	132		6,609

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Insurance (continued)
Assured Guaranty Ltd.	59	$	3,571
Employers Holdings, Inc.	163		6,512
Genworth Financial, Inc., Class A ^(a)	3,842		22,514
Horace Mann Educators Corp.	56		1,645
James River Group Holdings Ltd.	526		8,074
Mercury General Corp.	168		4,709
NMI Holdings, Inc., Class A ^(a)	1,016		27,524
Palomar Holdings, Inc. ^(a)	200		10,150
ProAssurance Corp.	89		1,681
Safety Insurance Group, Inc.	23		1,568
SiriusPoint Ltd. ^(a)	1,274		12,957
Stewart Information Services Corp.	269		11,782
United Fire Group, Inc.	155		3,061
Universal Insurance Holdings, Inc.	463		6,491
		$	161,459

Internet — 1.19%
Cars.com, Inc. ^(a)	280		4,721
Cogent Communications Holdings, Inc.	173		10,709
ePlus, Inc. ^(a)	274		17,405
HealthStream, Inc.	356		7,683
Liquidity Services, Inc. ^(a)	326		5,744
Perficient, Inc. ^(a)	140		8,100
QuinStreet, Inc. ^(a)	289		2,592
Shutterstock, Inc.	83		3,158
TechTarget, Inc. ^(a)	125		3,795
Yelp, Inc. ^(a)	77		3,202
		$	67,109

Iron & Steel — 0.57%
ATI, Inc. ^(a)	322		13,250
Carpenter Technology Corp.	165		11,090
Haynes International, Inc.	164		7,629
		$	31,969

Leisure Time — 0.18%
Vista Outdoor, Inc. ^(a)	311		10,300

Lodging — 0.16%
Marcus Corp.	591		9,161

Machinery — Construction & Mining — 0.10%
Astec Industries, Inc.	119		5,606

Machinery — Diversified — 1.95%
Alamo Group, Inc.	84		14,520
Albany International Corp., Class A	124		10,698
Applied Industrial Technologies, Inc.	223		34,478
CIRCOR International, Inc. ^(a)	137		7,638
DXP Enterprises, Inc. ^(a)	367		12,823
Ichor Holdings Ltd. ^(a)	329		10,186
Lindsay Corp.	54		6,355
Tennant Co.	185		13,718
		$	110,416

Media — 0.46%
AMC Networks, Inc., Class A ^(a)	282		3,322
EW Scripps Co., Class A ^(a)	928		5,085
Scholastic Corp.	319		12,167

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Media (continued)
Thryv Holdings, Inc. ^(a)	282	$	5,293
		$	25,867

Metal Fabrication & Hardware — 1.49%
AZZ, Inc.	264		12,033
Mueller Industries, Inc.	504		37,881
Olympic Steel, Inc.	168		9,443
Standex International Corp.	110		16,026
TimkenSteel Corp. ^(a)	274		5,951
Tredegar Corp.	586		3,170
		$	84,504

Miscellaneous Manufacturers — 2.18%
EnPro Industries, Inc.	24		2,909
Fabrinet ^(a)	223		37,156
Federal Signal Corp.	402		24,011
Hillenbrand, Inc.	257		10,874
John Bean Technologies Corp.	207		21,764
Materion Corp.	129		13,146
Myers Industries, Inc.	657		11,780
Sturm Ruger & Co., Inc.	29		1,512
		$	123,152

Office & Business Equipment — 0.13%
Pitney Bowes, Inc.	2,493		7,529

Office Furnishings — 0.38%
HNI Corp.	465		16,103
Interface, Inc.	567		5,562
		$	21,665

Oil & Gas — 2.92%
Callon Petroleum Co. ^(a)	398		15,570
Civitas Resources, Inc.	299		24,180
Comstock Resources, Inc.	938		10,346
CVR Energy, Inc.	490		16,674
Nabors Industries Ltd. ^(a)	50		6,157
Northern Oil & Gas, Inc.	491		19,753
Par Pacific Holdings, Inc. ^(a)	661		23,756
Patterson-UTI Energy, Inc.	733		10,145
SM Energy Co.	378		14,988
Talos Energy, Inc. ^(a)	1,061		17,443
Vital Energy, Inc. ^(a)	117		6,484
		$	165,496

Oil & Gas Services — 1.38%
Archrock, Inc.	570		7,182
Bristow Group, Inc. ^(a)	214		6,028
DMC Global, Inc. ^(a)	393		9,617
Dril-Quip, Inc. ^(a)	175		4,930
Helix Energy Solutions Group, Inc. ^(a)	683		7,629
NOW, Inc. ^(a)	1,031		12,238
Oceaneering International, Inc. ^(a)	371		9,542
Oil States International, Inc. ^(a)	517		4,327
RPC, Inc.	1,126		10,067
U.S. Silica Holdings, Inc. ^(a)	457		6,416
		$	77,976

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Packaging & Containers — 0.57%
Clearwater Paper Corp. ^(a)	275	$	9,969
O-I Glass, Inc. ^(a)	1,324		22,150
		$	32,119

Pharmaceuticals — 1.83%
AdaptHealth Corp. ^(a)	358		3,258
Amphastar Pharmaceuticals, Inc. ^(a)	193		8,876
Anika Therapeutics, Inc. ^(a)	133		2,478
Catalyst Pharmaceuticals, Inc. ^(a)	710		8,300
Collegium Pharmaceutical, Inc. ^(a)	188		4,202
Corcept Therapeutics, Inc. ^(a)	304		8,282
Eagle Pharmaceuticals, Inc. ^(a)	153		2,413
Harmony Biosciences Holdings, Inc. ^(a)	123		4,031
Ironwood Pharmaceuticals, Inc. ^(a)	1,341		12,914
Owens & Minor, Inc. ^(a)	431		6,965
Pacira BioSciences, Inc. ^(a)	52		1,595
Phibro Animal Health Corp., Class A	544		6,947
Prestige Consumer Healthcare, Inc. ^(a)	333		19,044
Supernus Pharmaceuticals, Inc. ^(a)	248		6,837
uniQure NV ^(a)	226		1,516
USANA Health Sciences, Inc. ^(a)	103		6,037
		$	103,695

Real Estate — 0.35%
Cushman & Wakefield PLC ^(a)	668		5,090
Douglas Elliman, Inc.	1,377		3,112
Kennedy-Wilson Holdings, Inc.	134		1,975
Marcus & Millichap, Inc.	49		1,438
RE/MAX Holdings, Inc., Class A	433		5,603
St. Joe Co.	47		2,554
		$	19,772

REITs — 5.04%
Acadia Realty Trust	133		1,909
Alexander & Baldwin, Inc.	100		1,673
American Assets Trust, Inc.	89		1,731
Apollo Commercial Real Estate Finance, Inc.	1,219		12,348
Armada Hoffler Properties, Inc.	939		9,615
ARMOUR Residential REIT, Inc.	1,193		5,070
Brandywine Realty Trust	1,159		5,262
CareTrust REIT, Inc.	461		9,450
Centerspace	27		1,627
Chatham Lodging Trust	131		1,254
Community Healthcare Trust, Inc.	171		5,079
DiamondRock Hospitality Co.	1,136		9,122
Easterly Government Properties, Inc.	514		5,875
Ellington Financial, Inc.	125		1,559
Elme Communities	131		1,787
Essential Properties Realty Trust, Inc.	921		19,921
Four Corners Property Trust, Inc.	642		14,246
Franklin BSP Realty Trust, Inc.	554		7,335
Getty Realty Corp.	377		10,454
Global Net Lease, Inc.	583		5,603
Hudson Pacific Properties, Inc.	863		5,739
Innovative Industrial Properties, Inc.	92		6,961
JBG SMITH Properties	130		1,880
KKR Real Estate Finance Trust, Inc.	127		1,507
LTC Properties, Inc.	393		12,627

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

REITs (continued)
LXP Industrial Trust	271	$	2,412
NexPoint Residential Trust, Inc.	45		1,448
Office Properties Income Trust	402		1,648
Orion Office REIT, Inc.	201		1,047
PennyMac Mortgage Investment Trust	139		1,724
Ready Capital Corp.	1,214		12,274
Redwood Trust, Inc.	205		1,462
Retail Opportunity Investments Corp.	592		7,329
RPT Realty	719		7,593
Safehold, Inc.	140		2,492
Saul Centers, Inc.	132		4,656
Service Properties Trust	1,335		10,266
SITE Centers Corp.	191		2,355
Summit Hotel Properties, Inc.	750		4,350
Sunstone Hotel Investors, Inc.	241		2,253
Tanger Factory Outlet Centers, Inc.	473		10,690
Two Harbors Investment Corp.	1,001		13,253
Uniti Group, Inc.	1,504		7,099
Universal Health Realty Income Trust	194		7,843
Urban Edge Properties	143		2,182
Veris Residential, Inc.	485		8,003
Whitestone REIT	537		5,171
Xenia Hotels & Resorts, Inc.	657		7,739
		$	284,923

Retail — 8.41%
Abercrombie & Fitch Co., Class A ^(a)	213		12,007
Academy Sports & Outdoors, Inc.	589		27,842
America's Car-Mart, Inc. ^(a)	111		10,100
American Eagle Outfitters, Inc.	609		10,115
Asbury Automotive Group, Inc. ^(a)	173		39,802
BJ's Restaurants, Inc. ^(a)	147		3,449
Bloomin' Brands, Inc.	704		17,311
Boot Barn Holdings, Inc. ^(a)	93		7,551
Brinker International, Inc. ^(a)	362		11,436
Buckle, Inc.	333		11,119
Caleres, Inc.	443		12,741
Cheesecake Factory, Inc.	179		5,424
Chico's FAS, Inc. ^(a)	1,703		12,738
Children's Place, Inc. ^(a)	120		3,244
Chuy's Holdings, Inc. ^(a)	160		5,693
Cracker Barrel Old Country Store, Inc.	93		6,250
Dave & Buster's Entertainment, Inc. ^(a)	336		12,455
Designer Brands, Inc., Class A	513		6,495
Dine Brands Global, Inc.	181		8,950
El Pollo Loco Holdings, Inc.	429		3,839
Genesco, Inc. ^(a)	224		6,904
GMS, Inc. ^(a)	458		29,298
Group 1 Automotive, Inc.	128		34,395
Guess?, Inc.	330		7,141
Haverty Furniture Cos., Inc.	427		12,289
Hibbett, Inc.	239		11,355
Jack in the Box, Inc.	84		5,801
La-Z-Boy, Inc.	587		18,127
Leslie's, Inc. ^(a)	534		3,022
MarineMax, Inc. ^(a)	326		10,699
Movado Group, Inc.	159		4,349
Nu Skin Enterprises, Inc., Class A	55		1,167

See accompanying notes.


	Schedule of Investments
Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Retail (continued)
ODP Corp. ^(a)	353	$	16,291
Patrick Industries, Inc.	295		22,143
PC Connection, Inc.	190		10,142
PriceSmart, Inc.	219		16,300
Sally Beauty Holdings, Inc. ^(a)	838		7,022
Shoe Carnival, Inc.	323		7,762
Signet Jewelers Ltd.	135		9,694
Sonic Automotive, Inc., Class A	191		9,122
Zumiez, Inc. ^(a)	233		4,147
		$	475,731

Savings & Loans — 2.33%
Axos Financial, Inc. ^(a)	387		14,652
Banc of California, Inc.	818		10,127
Berkshire Hills Bancorp, Inc.	516		10,346
Brookline Bancorp, Inc.	1,070		9,748
Capitol Federal Financial, Inc.	213		1,016
Northfield Bancorp, Inc.	1,089		10,291
Northwest Bancshares, Inc.	1,127		11,529
Pacific Premier Bancorp, Inc.	731		15,907
Provident Financial Services, Inc.	729		11,146
Washington Federal, Inc.	767		19,650
WSFS Financial Corp.	470		17,155
		$	131,567

Semiconductors — 2.84%
Alpha & Omega Semiconductor Ltd. ^(a)	180		5,371
Axcelis Technologies, Inc. ^(a)	171		27,882
Cohu, Inc. ^(a)	227		7,818
Diodes, Inc. ^(a)	247		19,473
Kulicke & Soffa Industries, Inc.	344		16,729
MaxLinear, Inc. ^(a)	209		4,650
Onto Innovation, Inc. ^(a)	125		15,940
Photronics, Inc. ^(a)	638		12,894
Rambus, Inc. ^(a)	364		20,308
Semtech Corp. ^(a)	454		11,690
SMART Global Holdings, Inc. ^(a)	317		7,719
Veeco Instruments, Inc. ^(a)	363		10,204
		$	160,678

Software — 2.84%
Adeia, Inc.	1,781		19,021
Agilysys, Inc. ^(a)	74		4,896
Avid Technology, Inc. ^(a)	153		4,111
Computer Programs & Systems, Inc. ^(a)	311		4,957
Consensus Cloud Solutions, Inc. ^(a)	146		3,676
CSG Systems International, Inc.	147		7,515
Digi International, Inc. ^(a)	371		10,017
Digital Turbine, Inc. ^(a)	484		2,928
Donnelley Financial Solutions, Inc. ^(a)	262		14,745
DoubleVerify Holdings, Inc. ^(a)	484		13,528
Ebix, Inc.	575		5,681
NextGen Healthcare, Inc. ^(a)	349		8,282
PDF Solutions, Inc. ^(a)	128		4,147
Progress Software Corp.	314		16,510
Simulations Plus, Inc.	93		3,878
SPS Commerce, Inc. ^(a)	117		19,962
Veradigm, Inc. ^(a)	476		6,255

See accompanying notes.


		Schedule of Investments
	Principal U.S. Small-Cap Adaptive Multi-Factor ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value
Software (continued)
Verra Mobility Corp. ^(a)		563	$	10,528
			$	160,637

Telecommunications — 0.86%
A10 Networks, Inc.		104		1,563
ATN International, Inc.		98		3,093
Clearfield, Inc. ^(a)		84		2,407
Extreme Networks, Inc. ^(a)		410		9,926
Harmonic, Inc. ^(a)		418		4,025
InterDigital, Inc.		183		14,684
Lumen Technologies, Inc. ^(a)		3,203		4,548
NETGEAR, Inc. ^(a)		75		944
Shenandoah Telecommunications Co.		255		5,256
Viavi Solutions, Inc. ^(a)		233		2,130
			$	48,576

Textiles — 0.17%
UniFirst Corp.		60		9,781
Transportation — 2.54%
ArcBest Corp.		162		16,467
Dorian LPG Ltd.		205		5,890
Forward Air Corp.		188		12,923
Heartland Express, Inc.		992		14,573
Hub Group, Inc., Class A ^(a)		336		26,389
Marten Transport Ltd.		607		11,964
Matson, Inc.		253		22,446
RXO, Inc. ^(a)		810		15,981
World Kinect Corp.		753		16,890
			$	143,523

Water — 0.98%
American States Water Co.		243		19,119
California Water Service Group		365		17,268
Middlesex Water Co.		96		6,360
SJW Group		209		12,563

			$	55,310
TOTAL COMMON STOCKS			$	5,630,072
INVESTMENT COMPANIES — 0.42%		Shares Held		Value
Money Market Fund — 0.42%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)		23,890	$	23,890
TOTAL INVESTMENT COMPANIES			$	23,890
Total Investments			$	5,653,962
Other Assets and Liabilities — 0.09%				4,830
Total Net Assets — 100.00%			$	5,658,792

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.




See accompanying notes.		84


	Schedule of Investments
	Principal U.S. Small-Cap Adaptive Multi-Factor ETF
	September 30, 2023 (unaudited)

	Portfolio Summary
Sector	Percent
Financial	23.23	%
Industrial	20.42	%
Consumer, Cyclical	18.24	%
Consumer, Non-cyclical	16.80	%
Technology	6.76	%
Energy	5.86	%
Basic Materials	3.52	%
Communications	2.50	%
Utilities	2.16	%
Money Market Fund	0.42	%
Other Assets and Liabilities	0.09	%
TOTAL NET ASSETS	100.00	%

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.56%		Shares Held		Value

Advertising — 0.02%
Stagwell, Inc. ^(a)		11,287	$	52,936

Aerospace & Defense — 0.24%
Barnes Group, Inc.		7,783		264,389
Moog, Inc., Class A		3,945		445,627
			$	710,016

Agriculture — 0.08%
Fresh Del Monte Produce, Inc.		4,575		118,218
Turning Point Brands, Inc.		4,812		111,109
			$	229,327

Apparel — 1.18%
Crocs, Inc. ^(a)		16,731		1,476,176
Ermenegildo Zegna NV		4,956		68,988
Kontoor Brands, Inc.		7,377		323,924
Oxford Industries, Inc.		2,770		266,280
Steven Madden Ltd.		13,678		434,550
Urban Outfitters, Inc. ^(a)		29,573		966,741
			$	3,536,659

Auto Manufacturers — 0.14%
Wabash National Corp.		20,400		430,848

Auto Parts & Equipment — 0.62%
Dorman Products, Inc. ^(a)		2,309		174,930
Fox Factory Holding Corp. ^(a)		3,259		322,902
Methode Electronics, Inc.		4,957		113,267
Shyft Group, Inc.		9,447		141,422
Standard Motor Products, Inc.		2,361		79,377
Visteon Corp. ^(a)		5,606		774,020
XPEL, Inc. ^(a)		3,213		247,754
			$	1,853,672

Banks — 4.61%
1st Source Corp.		2,682		112,885
Amalgamated Financial Corp.		9,094		156,599
Ameris Bancorp		20,314		779,855
Associated Banc-Corp.		98,549		1,686,173
Atlantic Union Bankshares Corp.		16,171		465,401
Bancorp, Inc. ^(a)		15,926		549,447
Bank of NT Butterfield & Son Ltd.		9,685		262,270
Cadence Bank		74,740		1,585,983
Central Pacific Financial Corp.		10,114		168,702
City Holding Co.		3,563		321,917
Enterprise Financial Services Corp.		8,092		303,450
First BanCorp		68,511		922,158
First BanCorp/Southern Pines NC		11,152		313,817
First Bancshares, Inc.		7,672		206,914
First Financial Bancorp		15,478		303,369
First Foundation, Inc.		19,388		117,879
Heartland Financial USA, Inc.		8,838		260,102
Hilltop Holdings, Inc.		19,512		553,360
International Bancshares Corp.		12,764		553,192
NBT Bancorp, Inc.		10,735		340,192
Pathward Financial, Inc.		13,273		611,753
Peoples Bancorp, Inc.		6,581		167,026
Preferred Bank		4,576		284,856

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Banks (continued)
Premier Financial Corp.		7,531	$	128,479
Renasant Corp.		11,065		289,792
S&T Bancorp, Inc.		8,187		221,704
Tompkins Financial Corp.		2,021		99,009
Towne Bank		9,656		221,412
TriCo Bancshares		4,140		132,604
United Bankshares, Inc.		26,165		721,892
United Community Banks, Inc.		31,893		810,401
WesBanco, Inc.		8,086		197,460
			$	13,850,053

Beverages — 0.54%
Coca-Cola Consolidated, Inc.		1,066		678,317
Duckhorn Portfolio, Inc. ^(a)		12,222		125,398
MGP Ingredients, Inc.		3,539		373,294
Primo Water Corp.		23,646		326,315
Vita Coco Co., Inc. ^(a)		4,855		126,424
			$	1,629,748

Biotechnology — 3.11%
ACADIA Pharmaceuticals, Inc. ^(a)		44,242		922,003
ADMA Biologics, Inc. ^(a)		72,915		261,036
Amicus Therapeutics, Inc. ^(a)		71,193		865,707
Arcus Biosciences, Inc. ^(a)		31,006		556,558
Avid Bioservices, Inc. ^(a)		7,312		69,025
Bridgebio Pharma, Inc. ^(a)		9,567		252,282
Chinook Therapeutics, Inc. ^(a),(b)		9,658		3,863
Cytek Biosciences, Inc. ^(a)		24,292		134,092
Dynavax Technologies Corp. ^(a)		47,136		696,199
Emergent BioSolutions, Inc. ^(a)		23,802		80,927
Halozyme Therapeutics, Inc. ^(a)		50,574		1,931,927
Innoviva, Inc. ^(a)		20,771		269,815
Intercept Pharmaceuticals, Inc. ^(a)		28,802		533,989
iTeos Therapeutics, Inc. ^(a)		9,811		107,430
Ligand Pharmaceuticals, Inc. ^(a)		3,682		220,625
Prothena Corp. PLC ^(a)		14,307		690,313
REGENXBIO, Inc. ^(a)		13,522		222,572
Rigel Pharmaceuticals, Inc. ^(a)		56,621		61,151
Syndax Pharmaceuticals, Inc. ^(a)		25,998		377,491
Veracyte, Inc. ^(a)		23,803		531,521
Vir Biotechnology, Inc. ^(a)		31,279		293,084
Xencor, Inc. ^(a)		12,788		257,678
			$	9,339,288

Building Materials — 2.07%
AAON, Inc.		11,881		675,672
American Woodmark Corp. ^(a)		4,102		310,152
Apogee Enterprises, Inc.		3,983		187,520
Boise Cascade Co.		9,981		1,028,442
Gibraltar Industries, Inc. ^(a)		5,562		375,491
JELD-WEN Holding, Inc. ^(a)		18,078		241,522
Masonite International Corp. ^(a)		5,279		492,108
Modine Manufacturing Co. ^(a)		8,498		388,784
PGT Innovations, Inc. ^(a)		12,080		335,220
Summit Materials, Inc., Class A ^(a)		28,681		893,126
UFP Industries, Inc.		12,674		1,297,818
			$	6,225,855

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Chemicals — 1.09%
AdvanSix, Inc.		5,568	$	173,053
American Vanguard Corp.		4,986		54,497
Balchem Corp.		4,464		553,715
Ingevity Corp. ^(a)		11,576		551,133
Innospec, Inc.		3,961		404,814
Intrepid Potash, Inc. ^(a)		8,554		215,219
Koppers Holdings, Inc.		3,978		157,330
Quaker Chemical Corp.		3,548		567,680
Tronox Holdings PLC		44,420		597,005
			$	3,274,446

Coal — 2.50%
Alpha Metallurgical Resources, Inc.		10,383		2,696,777
Arch Resources, Inc.		8,570		1,462,556
CONSOL Energy, Inc.		14,714		1,543,646
Ramaco Resources, Inc., Class A		16,902		185,753
Ramaco Resources, Inc., Class B		3,380		40,323
SunCoke Energy, Inc.		35,027		355,524
Warrior Met Coal, Inc.		24,119		1,231,999
			$	7,516,578

Commercial Services — 7.23%
Adtalem Global Education, Inc. ^(a)		4,456		190,940
Alarm.com Holdings, Inc. ^(a)		7,673		469,127
AMN Healthcare Services, Inc. ^(a)		25,432		2,166,298
Barrett Business Services, Inc.		2,388		215,493
Brink's Co.		6,568		477,100
Carriage Services, Inc.		2,184		61,698
Cass Information Systems, Inc.		2,747		102,326
CBIZ, Inc. ^(a)		7,382		383,126
Chegg, Inc. ^(a)		55,752		497,308
CorVel Corp. ^(a)		2,174		427,517
CRA International, Inc.		2,787		280,818
Cross Country Healthcare, Inc. ^(a)		23,954		593,820
Ennis, Inc.		4,825		102,387
EVERTEC, Inc.		17,212		639,942
First Advantage Corp.		11,794		162,639
GEO Group, Inc. ^(a)		99,538		814,221
Green Dot Corp., Class A ^(a)		14,987		208,769
Hackett Group, Inc.		8,060		190,135
Heidrick & Struggles International, Inc.		4,392		109,888
Herc Holdings, Inc.		14,260		1,696,084
Huron Consulting Group, Inc. ^(a)		4,900		510,384
I3 Verticals, Inc., Class A ^(a)		7,093		149,946
Insperity, Inc.		6,758		659,581
John Wiley & Sons, Inc., Class A		8,529		317,023
Kforce, Inc.		5,444		324,789
Korn Ferry		9,956		472,313
Matthews International Corp., Class A		4,833		188,052
Medifast, Inc.		5,874		439,669
Monro, Inc.		5,398		149,902
Payoneer Global, Inc. ^(a)		117,260		717,631
Perdoceo Education Corp.		8,352		142,819
Progyny, Inc. ^(a)		26,282		894,114
R1 RCM, Inc. ^(a)		65,439		986,166
Repay Holdings Corp. ^(a)		45,694		346,817
Resources Connection, Inc.		8,231		122,724
SP Plus Corp. ^(a)		3,664		132,270

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Commercial Services (continued)
StoneCo Ltd., Class A ^(a)		220,855	$	2,356,523
Strategic Education, Inc.		2,211		166,378
Stride, Inc. ^(a)		8,816		396,984
Target Hospitality Corp. ^(a),(c)		14,393		228,561
Transcat, Inc. ^(a)		2,312		226,507
TriNet Group, Inc. ^(a)		12,605		1,468,230
V2X, Inc. ^(a)		2,755		142,323
ZipRecruiter, Inc., Class A ^(a)		33,915		406,641
			$	21,735,983

Computers — 3.80%
ExlService Holdings, Inc. ^(a)		34,980		980,839
Insight Enterprises, Inc. ^(a)		8,080		1,175,640
Integral Ad Science Holding Corp. ^(a)		8,820		104,870
Maximus, Inc.		13,504		1,008,479
Mitek Systems, Inc. ^(a)		12,611		135,190
Parsons Corp. ^(a)		19,580		1,064,173
Qualys, Inc. ^(a)		10,145		1,547,620
Super Micro Computer, Inc. ^(a)		19,720		5,407,618
			$	11,424,429

Cosmetics & Personal Care — 1.03%
Edgewell Personal Care Co.		9,362		346,019
elf Beauty, Inc. ^(a)		21,013		2,307,858
Inter Parfums, Inc.		3,381		454,204
			$	3,108,081

Distribution & Wholesale — 0.14%
Rush Enterprises, Inc., Class A		10,546		430,593

Distribution/Wholesale — 0.26%
G-III Apparel Group Ltd. ^(a)		13,119		326,925
ScanSource, Inc. ^(a)		4,565		138,365
Titan Machinery, Inc. ^(a)		12,329		327,705
			$	792,995

Diversified Financial Services — 4.83%
AssetMark Financial Holdings, Inc. ^(a)		4,522		113,412
BGC Group, Inc., Class A		69,803		368,560
Enact Holdings, Inc.		5,773		157,199
Enova International, Inc. ^(a)		11,775		598,994
EZCORP, Inc., Class A ^(a)		25,178		207,718
Federal Agricultural Mortgage Corp., Class C		3,418		527,397
Federated Hermes, Inc.		32,493		1,100,538
Houlihan Lokey, Inc.		19,316		2,069,130
International Money Express, Inc. ^(a)		14,847		251,360
LendingTree, Inc. ^(a)		11,733		181,861
Moelis & Co., Class A		31,564		1,424,483
Nelnet, Inc., Class A		1,927		172,120
PennyMac Financial Services, Inc.		17,217		1,146,652
Perella Weinberg Partners		14,541		148,027
Piper Sandler Cos.		5,402		784,964
PJT Partners, Inc., Class A		10,081		800,835
Radian Group, Inc.		65,409		1,642,420
StepStone Group, Inc., Class A		16,284		514,249
StoneX Group, Inc. ^(a)		5,779		560,101
Victory Capital Holdings, Inc., Class A		17,923		597,553
Virtus Investment Partners, Inc.		4,010		809,980

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Diversified Financial Services (continued)
World Acceptance Corp. ^(a)	2,599	$	330,229
		$	14,507,782

Electric — 1.69%
ALLETE, Inc.	17,212		908,794
Otter Tail Corp.	9,997		758,972
PNM Resources, Inc.	36,431		1,625,187
Portland General Electric Co.	39,797		1,610,982
Unitil Corp.	4,015		171,481
		$	5,075,416

Electrical Components & Equipment — 1.15%
Belden, Inc.	9,241		892,219
Encore Wire Corp.	6,276		1,145,119
Energizer Holdings, Inc.	13,420		429,977
Insteel Industries, Inc.	4,116		133,605
Novanta, Inc. ^(a)	4,278		613,636
Powell Industries, Inc.	3,069		254,420
		$	3,468,976

Electronics — 2.71%
Advanced Energy Industries, Inc.	6,523		672,652
Allient, Inc.	2,536		78,413
Atkore, Inc. ^(a)	14,756		2,201,448
Badger Meter, Inc.	4,132		594,471
Benchmark Electronics, Inc.	8,500		206,210
Brady Corp., Class A	7,327		402,399
CTS Corp.	5,706		238,168
ESCO Technologies, Inc.	3,187		332,850
Knowles Corp. ^(a)	24,870		368,325
Mesa Laboratories, Inc.	1,637		172,000
Napco Security Technologies, Inc.	11,125		247,531
OSI Systems, Inc. ^(a)	3,251		383,748
Plexus Corp. ^(a)	5,419		503,859
Sanmina Corp. ^(a)	13,733		745,427
TTM Technologies, Inc. ^(a)	19,097		245,969
Vishay Intertechnology, Inc.	29,997		741,526
		$	8,134,996

Energy — Alternate Sources — 0.07%
Montauk Renewables, Inc. ^(a)	16,297		148,466
REX American Resources Corp. ^(a)	1,793		73,011
		$	221,477

Engineering & Construction — 2.14%
Arcosa, Inc.	6,896		495,822
Comfort Systems USA, Inc.	7,811		1,331,073
EMCOR Group, Inc.	9,824		2,066,871
Exponent, Inc.	6,374		545,614
Frontdoor, Inc. ^(a)	14,111		431,656
MYR Group, Inc. ^(a)	2,960		398,890
NV5 Global, Inc. ^(a)	4,258		409,747
Sterling Infrastructure, Inc. ^(a)	10,152		745,969
		$	6,425,642

Entertainment — 0.23%
Atlanta Braves Holdings, Inc., Class C ^(a)	3,782		135,131

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Entertainment (continued)
Monarch Casino & Resort, Inc.		1,954	$	121,343
RCI Hospitality Holdings, Inc.		1,738		105,427
Red Rock Resorts, Inc., Class A		7,939		325,499
			$	687,400

Environmental Control — 0.14%
Energy Recovery, Inc. ^(a)		9,658		204,846
Heritage-Crystal Clean, Inc. ^(a)		4,676		212,057
			$	416,903

Food — 1.22%
Hostess Brands, Inc. ^(a)		24,376		811,965
Lancaster Colony Corp.		4,287		707,484
Simply Good Foods Co. ^(a)		13,539		467,366
Sprouts Farmers Market, Inc. ^(a)		33,969		1,453,873
Tootsie Roll Industries, Inc.		3,070		91,670
Weis Markets, Inc.		2,200		138,600
			$	3,670,958

Forest Products & Paper — 0.25%
Sylvamo Corp.		17,338		761,832

Gas — 0.31%
New Jersey Resources Corp.		22,748		924,251

Hand/Machine Tools — 0.35%
Franklin Electric Co., Inc.		5,102		455,252
Kennametal, Inc.		23,514		585,028
			$	1,040,280

Healthcare — Products — 4.21%
Alphatec Holdings, Inc. ^(a)		24,527		318,115
Avanos Medical, Inc. ^(a)		6,871		138,932
CONMED Corp.		9,672		975,421
Embecta Corp.		16,565		249,303
Haemonetics Corp. ^(a)		11,033		988,336
Integer Holdings Corp. ^(a)		7,568		593,558
Lantheus Holdings, Inc. ^(a)		23,657		1,643,688
LeMaitre Vascular, Inc.		2,319		126,339
LivaNova PLC ^(a)		17,652		933,438
Merit Medical Systems, Inc. ^(a)		7,611		525,311
Neogen Corp. ^(a)		58,658		1,087,519
OmniAb, Inc., Earnout Shares ^(a)		1,130		—
OmniAb, Inc., Earnout Shares ^(a)		1,130		—
Omnicell, Inc. ^(a)		12,773		575,296
OraSure Technologies, Inc. ^(a)		15,742		93,350
Orthofix Medical, Inc. ^(a)		10,757		138,335
Shockwave Medical, Inc. ^(a)		9,732		1,937,641
Silk Road Medical, Inc. ^(a)		17,813		267,017
STAAR Surgical Co. ^(a)		19,844		797,332
Tactile Systems Technology, Inc. ^(a)		4,878		68,536
TransMedics Group, Inc. ^(a)		10,474		573,452
UFP Technologies, Inc. ^(a)		2,316		373,918
Varex Imaging Corp. ^(a)		7,930		149,005
Zimvie, Inc. ^(a)		5,545		52,179
Zynex, Inc. ^(a)		6,638		53,104
			$	12,659,125

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Healthcare — Services — 2.20%
Addus HomeCare Corp. ^(a)	2,626	$	223,709
Agiliti, Inc. ^(a)	7,775		50,460
Cano Health, Inc. ^(a)	95,426		24,200
DocGo, Inc. ^(a)	17,391		92,694
Ensign Group, Inc.	7,466		693,815
Fulgent Genetics, Inc. ^(a)	6,425		171,804
HealthEquity, Inc. ^(a)	23,374		1,707,471
Medpace Holdings, Inc. ^(a)	10,381		2,513,551
ModivCare, Inc. ^(a)	3,517		110,821
Pediatrix Medical Group, Inc. ^(a)	21,456		272,706
RadNet, Inc. ^(a)	5,157		145,376
Select Medical Holdings Corp.	15,010		379,303
U.S. Physical Therapy, Inc.	2,522		231,343
		$	6,617,253

Home Builders — 2.33%
Beazer Homes USA, Inc. ^(a)	4,710		117,326
Cavco Industries, Inc. ^(a)	1,180		313,479
Century Communities, Inc.	5,026		335,636
Green Brick Partners, Inc. ^(a)	5,142		213,445
Hovnanian Enterprises, Inc., Class A ^(a)	1,502		152,693
Installed Building Products, Inc.	4,182		522,290
KB Home	24,871		1,151,030
LGI Homes, Inc. ^(a)	3,823		380,350
M/I Homes, Inc. ^(a)	4,971		417,763
MDC Holdings, Inc.	10,155		418,691
Meritage Homes Corp.	7,090		867,745
Skyline Champion Corp. ^(a)	6,474		412,523
Taylor Morrison Home Corp. ^(a)	15,514		661,052
Tri Pointe Homes, Inc. ^(a)	15,128		413,751
Winnebago Industries, Inc.	10,412		618,993
		$	6,996,767

Home Furnishings — 0.26%
Ethan Allen Interiors, Inc.	5,282		157,932
MillerKnoll, Inc.	18,955		463,449
Sleep Number Corp. ^(a)	5,871		144,368
		$	765,749

Household Products/Wares — 0.57%
ACCO Brands Corp.	24,261		139,258
Helen of Troy Ltd. ^(a)	8,847		1,031,206
WD-40 Co.	2,640		536,554
		$	1,707,018

Insurance — 4.29%
Ambac Financial Group, Inc. ^(a)	20,683		249,437
American Equity Investment Life Holding Co. ^(a)	35,285		1,892,687
CNO Financial Group, Inc.	47,673		1,131,280
Essent Group Ltd.	26,471		1,251,814
Jackson Financial, Inc., Class A	56,404		2,155,761
Kinsale Capital Group, Inc.	7,020		2,907,193
NMI Holdings, Inc., Class A ^(a)	17,392		471,149
Palomar Holdings, Inc. ^(a)	6,330		321,247
RLI Corp.	8,490		1,153,706
Selective Insurance Group, Inc.	12,486		1,288,181

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Insurance (continued)
Universal Insurance Holdings, Inc.		5,584	$	78,288
			$	12,900,743

Internet — 1.86%
1-800-Flowers.com, Inc., Class A ^(a)		6,782		47,474
Cargurus, Inc. ^(a)		37,033		648,818
Cars.com, Inc. ^(a)		12,643		213,161
Figs, Inc., Class A ^(a)		76,551		451,651
HealthStream, Inc.		2,905		62,690
Open Lending Corp., Class A ^(a)		29,962		219,322
Perficient, Inc. ^(a)		7,069		409,012
Q2 Holdings, Inc. ^(a)		17,658		569,824
QuinStreet, Inc. ^(a)		9,887		88,686
Revolve Group, Inc. ^(a)		22,388		304,701
Shutterstock, Inc.		15,993		608,533
Squarespace, Inc., Class A ^(a)		17,460		505,816
Yelp, Inc. ^(a)		19,525		812,045
Ziff Davis, Inc. ^(a)		10,365		660,147
			$	5,601,880

Iron & Steel — 0.76%
Commercial Metals Co.		43,119		2,130,510
Haynes International, Inc.		3,544		164,867
			$	2,295,377

Leisure Time — 0.17%
Acushnet Holdings Corp.		6,164		326,939
Malibu Boats, Inc., Class A ^(a)		2,168		106,275
MasterCraft Boat Holdings, Inc. ^(a)		3,979		88,413
			$	521,627

Machinery — Construction & Mining — 0.68%
Terex Corp.		35,433		2,041,649

Machinery — Diversified — 1.68%
Alamo Group, Inc.		2,051		354,536
Albany International Corp., Class A		6,075		524,151
Applied Industrial Technologies, Inc.		8,237		1,273,522
CSW Industrials, Inc.		2,974		521,164
GrafTech International Ltd.		60,417		231,397
Kadant, Inc.		2,487		560,943
Mueller Water Products, Inc., Class A		28,704		363,967
Tennant Co.		2,522		187,006
Thermon Group Holdings, Inc. ^(a)		7,189		197,482
Watts Water Technologies, Inc., Class A		4,819		832,820
			$	5,046,988

Media — 0.31%
AMC Networks, Inc., Class A ^(a)		7,895		93,003
Gray Television, Inc.		33,080		228,913
Liberty Latin America Ltd., Class C ^(a)		42,805		349,289
Sinclair, Inc.		23,972		268,966
			$	940,171

Metal Fabrication & Hardware — 1.22%
Mueller Industries, Inc.		13,552		1,018,568
Olympic Steel, Inc.		5,000		281,050
Proto Labs, Inc. ^(a)		7,914		208,930

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Metal Fabrication & Hardware (continued)
RBC Bearings, Inc. ^(a)		6,493	$	1,520,206
Ryerson Holding Corp.		10,545		306,754
Standex International Corp.		2,351		342,517
			$	3,678,025

Mining — 0.21%
Constellium SE ^(a)		34,804		633,433

Miscellaneous Manufacturers — 1.05%
Fabrinet ^(a)		7,196		1,198,997
Federal Signal Corp.		12,123		724,107
Hillenbrand, Inc.		12,254		518,467
Materion Corp.		4,580		466,748
Smith & Wesson Brands, Inc.		9,985		128,906
Sturm Ruger & Co., Inc.		2,158		112,475
			$	3,149,700

Office & Business Equipment — 0.26%
Xerox Holdings Corp.		49,534		777,188

Oil & Gas — 5.19%
Berry Corp.		13,970		114,554
California Resources Corp.		14,990		839,590
Callon Petroleum Co. ^(a)		26,906		1,052,563
Chord Energy Corp.		8,342		1,351,988
Civitas Resources, Inc.		10,721		867,007
Comstock Resources, Inc.		84,235		929,112
CVR Energy, Inc.		13,361		454,675
Denbury, Inc. ^(a)		9,673		948,051
Magnolia Oil & Gas Corp., Class A		32,173		737,083
Matador Resources Co.		24,706		1,469,513
Par Pacific Holdings, Inc. ^(a)		12,608		453,131
PBF Energy, Inc., Class A		45,805		2,451,942
Permian Resources Corp.		129,753		1,811,352
Ring Energy, Inc. ^(a)		48,961		95,474
Sitio Royalties Corp., Class A		13,058		316,134
Talos Energy, Inc. ^(a)		28,946		475,872
Weatherford International PLC ^(a)		13,519		1,221,171
			$	15,589,212

Oil & Gas Services — 0.71%
Archrock, Inc.		15,710		197,946
Aris Water Solutions, Inc., Class A		14,421		143,922
ChampionX Corp.		31,147		1,109,456
Expro Group Holdings NV ^(a)		14,116		327,915
Helix Energy Solutions Group, Inc. ^(a)		30,696		342,874
			$	2,122,113

Packaging & Containers — 0.40%
Greif, Inc., Class A		7,902		527,933
O-I Glass, Inc. ^(a)		40,696		680,844
			$	1,208,777

Pharmaceuticals — 3.05%
AbCellera Biologics, Inc. ^(a),(c)		54,276		249,670
AdaptHealth Corp. ^(a)		32,013		291,318
Alector, Inc. ^(a)		20,157		130,617
Alkermes PLC ^(a)		36,786		1,030,376

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Pharmaceuticals (continued)
Amphastar Pharmaceuticals, Inc. ^(a)		6,186	$	284,494
BellRing Brands, Inc. ^(a)		23,150		954,474
Catalyst Pharmaceuticals, Inc. ^(a)		41,717		487,672
Collegium Pharmaceutical, Inc. ^(a)		12,164		271,865
Corcept Therapeutics, Inc. ^(a)		23,007		626,826
Eagle Pharmaceuticals, Inc. ^(a)		4,751		74,923
Harmony Biosciences Holdings, Inc. ^(a)		20,116		659,201
Herbalife Ltd. ^(a)		41,703		583,425
Ironwood Pharmaceuticals, Inc. ^(a)		63,001		606,700
Option Care Health, Inc. ^(a)		30,569		988,907
Pacira BioSciences, Inc. ^(a)		15,749		483,179
PetIQ, Inc. ^(a)		8,214		161,816
Prestige Consumer Healthcare, Inc. ^(a)		7,765		444,080
Revance Therapeutics, Inc. ^(a)		10,172		116,673
Seres Therapeutics, Inc. ^(a)		23,350		55,573
SIGA Technologies, Inc.		27,816		146,034
Supernus Pharmaceuticals, Inc. ^(a)		12,324		339,773
USANA Health Sciences, Inc. ^(a)		1,896		111,125
Vanda Pharmaceuticals, Inc. ^(a)		17,524		75,704
			$	9,174,425

Pipelines — 0.05%
Kinetik Holdings, Inc. ^(c)		4,386		148,028

Real Estate — 0.61%
Cushman & Wakefield PLC ^(a)		126,288		962,315
Marcus & Millichap, Inc.		10,286		301,791
McGrath RentCorp		4,672		468,321
RE/MAX Holdings, Inc., Class A		8,529		110,365
			$	1,842,792

REITs — 5.16%
Agree Realty Corp.		30,788		1,700,729
American Assets Trust, Inc.		27,769		540,107
Broadstone Net Lease, Inc.		52,762		754,497
CareTrust REIT, Inc.		33,542		687,611
Community Healthcare Trust, Inc.		7,372		218,948
Easterly Government Properties, Inc.		52,270		597,446
Empire State Realty Trust, Inc., Class A		76,613		615,968
Essential Properties Realty Trust, Inc.		44,995		973,242
Four Corners Property Trust, Inc.		23,085		512,256
Getty Realty Corp.		15,903		440,990
Global Net Lease, Inc.		37,459		359,981
Industrial Logistics Properties Trust		65,667		189,778
Innovative Industrial Properties, Inc.		19,377		1,466,064
Office Properties Income Trust		34,990		143,459
Piedmont Office Realty Trust, Inc., Class A		93,157		523,542
PotlatchDeltic Corp.		25,260		1,146,551
STAG Industrial, Inc.		59,303		2,046,547
Tanger Factory Outlet Centers, Inc.		47,335		1,069,771
Terreno Realty Corp.		24,297		1,380,070
Universal Health Realty Income Trust		3,267		132,085
			$	15,499,642

Retail — 5.19%
Academy Sports & Outdoors, Inc.		21,436		1,013,280
Asbury Automotive Group, Inc. ^(a)		4,127		949,499
Bloomin' Brands, Inc.		26,632		654,881

See accompanying notes.


Schedule of Investments
Principal U.S. Small-Cap ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Retail (continued)
BlueLinx Holdings, Inc. ^(a)	3,931	$	322,696
Buckle, Inc.	9,573		319,642
Chuy's Holdings, Inc. ^(a)	2,102		74,789
Denny's Corp. ^(a)	12,314		104,300
Destination XL Group, Inc. ^(a)	16,296		73,006
Dillard's, Inc., Class A	2,897		958,357
FirstCash Holdings, Inc.	9,105		913,960
Foot Locker, Inc.	43,910		761,839
Genesco, Inc. ^(a)	4,102		126,424
GMS, Inc. ^(a)	8,530		545,664
Group 1 Automotive, Inc.	3,049		819,297
Haverty Furniture Cos., Inc.	2,790		80,296
Hibbett, Inc.	6,063		288,053
Jack in the Box, Inc.	5,900		407,454
La-Z-Boy, Inc.	6,472		199,855
MarineMax, Inc. ^(a)	10,143		332,893
Movado Group, Inc.	3,545		96,956
Murphy USA, Inc.	5,385		1,840,216
National Vision Holdings, Inc. ^(a)	15,736		254,609
OneWater Marine, Inc., Class A ^(a)	2,544		65,177
Patrick Industries, Inc.	3,187		239,216
PriceSmart, Inc.	2,777		206,692
Sally Beauty Holdings, Inc. ^(a)	23,359		195,748
Shoe Carnival, Inc.	6,945		166,888
Sonic Automotive, Inc., Class A	6,051		288,996
Texas Roadhouse, Inc.	14,738		1,416,322
Wingstop, Inc.	9,804		1,763,151
Winmark Corp.	284		105,969
		$	15,586,125

Savings & Loans — 0.30%
OceanFirst Financial Corp.	12,756		184,579
Washington Federal, Inc.	28,491		729,940
		$	914,519

Semiconductors — 3.91%
Amkor Technology, Inc.	38,071		860,405
Axcelis Technologies, Inc. ^(a)	15,808		2,577,494
Cohu, Inc. ^(a)	7,969		274,452
Diodes, Inc. ^(a)	7,038		554,876
Kulicke & Soffa Industries, Inc.	14,439		702,168
MACOM Technology Solutions Holdings, Inc. ^(a)	14,884		1,214,237
MaxLinear, Inc. ^(a)	16,749		372,665
Onto Innovation, Inc. ^(a)	7,157		912,661
Photronics, Inc. ^(a)	23,199		468,852
Power Integrations, Inc.	12,316		939,834
Rambus, Inc. ^(a)	28,597		1,595,427
Semtech Corp. ^(a)	45,235		1,164,801
Vishay Precision Group, Inc. ^(a)	3,252		109,202
		$	11,747,074

Software — 3.19%
8x8, Inc. ^(a)	39,069		98,454
ACI Worldwide, Inc. ^(a)	26,279		592,854
Adeia, Inc.	22,363		238,837
Agilysys, Inc. ^(a)	5,168		341,915
Apollo Medical Holdings, Inc. ^(a)	5,138		158,507
Avid Technology, Inc. ^(a)	7,667		206,012

See accompanying notes.


	Schedule of Investments
	Principal U.S. Small-Cap ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Software (continued)
CommVault Systems, Inc. ^(a)		10,837	$	732,690
Computer Programs & Systems, Inc. ^(a)		2,453		39,101
Digi International, Inc. ^(a)		10,185		274,995
Donnelley Financial Solutions, Inc. ^(a)		10,348		582,385
Ebix, Inc. ^(c)		18,645		184,213
EngageSmart, Inc. ^(a)		14,681		264,111
Envestnet, Inc. ^(a)		15,736		692,856
Everbridge, Inc. ^(a)		14,230		319,037
Health Catalyst, Inc. ^(a)		19,112		193,413
Model N, Inc. ^(a)		14,375		350,894
N-able, Inc. ^(a)		11,194		144,403
NextGen Healthcare, Inc. ^(a)		12,059		286,160
PDF Solutions, Inc. ^(a)		5,179		167,800
PowerSchool Holdings, Inc., Class A ^(a)		23,216		526,074
Privia Health Group, Inc. ^(a)		21,798		501,354
Progress Software Corp.		11,955		628,594
PubMatic, Inc., Class A ^(a)		15,399		186,328
Sapiens International Corp. NV		5,702		162,108
Simulations Plus, Inc.		2,938		122,515
SPS Commerce, Inc. ^(a)		4,541		774,740
Verra Mobility Corp. ^(a)		43,765		818,405
			$	9,588,755

Telecommunications — 1.60%
A10 Networks, Inc.		20,323		305,455
CommScope Holding Co., Inc. ^(a)		87,008		292,347
EchoStar Corp., Class A ^(a)		8,677		145,340
Extreme Networks, Inc. ^(a)		39,260		950,484
IDT Corp., Class B ^(a)		2,753		60,704
InterDigital, Inc.		11,468		920,192
Iridium Communications, Inc.		23,179		1,054,413
U.S. Cellular Corp. ^(a)		10,863		466,783
Viavi Solutions, Inc. ^(a)		66,081		603,980
			$	4,799,698

Textiles — 0.16%
UniFirst Corp.		2,893		471,588

Transportation — 3.45%
Air Transport Services Group, Inc. ^(a)		17,366		362,428
ArcBest Corp.		8,495		863,517
Covenant Logistics Group, Inc.		3,482		152,686
Dorian LPG Ltd.		11,202		321,834
FLEX LNG Ltd.		7,009		211,392
Forward Air Corp.		5,686		390,856
Heartland Express, Inc.		7,965		117,006
Hub Group, Inc., Class A ^(a)		7,847		616,303
International Seaways, Inc.		12,765		574,425
Marten Transport Ltd.		9,548		188,191
Matson, Inc.		11,445		1,015,400
Safe Bulkers, Inc. ^(c)		33,808		109,538
Saia, Inc. ^(a)		7,737		3,084,355
Scorpio Tankers, Inc.		26,445		1,431,203
Werner Enterprises, Inc.		20,092		782,583
World Kinect Corp.		7,038		157,862
			$	10,379,579

See accompanying notes.


		Schedule of Investments
		Principal U.S. Small-Cap ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)				Shares Held		Value

Water — 0.78%
American States Water Co.				8,970	$	705,760
Artesian Resources Corp., Class A				2,684		112,701
California Water Service Group				10,694		505,933
SJW Group				17,048		1,024,755
					$	2,349,149
TOTAL COMMON STOCKS					$	299,231,589
INVESTMENT COMPANIES — 0.59%				Shares Held		Value

Money Market Funds — 0.59%
Principal Government Money Market Fund — Class R-6 5.26% ^(d),(e),(f)				608,824	$	608,824
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(f)				1,170,177		1,170,177
TOTAL INVESTMENT COMPANIES					$	1,779,001
Total Investments					$	301,010,590
Other Assets and Liabilities — (0.15)%						(450,569	)

Total Net Assets — 100.00%					$	300,560,021

^(a)	Non-income producing security.
^(b)	The value of these investments was determined using significant unobservable inputs, in good faith by the Advisor, under
	procedures established and periodically reviewed by the Board of Trustees.
^(c)	Security or a portion of the security was on loan. At the end of the period, the value of these securities totaled $581,295 or
	0.19% of net assets.
^(d)	Affiliated Security. Security is either an affiliate (and registered under the Investment Company Act of 1940) or an affiliate
	as defined by the Investment Company Act of 1940 (controls 5.00% or more of the outstanding voting shares of the security).
	Please see Affiliated Securities sub-schedule for transactional information.
^(e)	Security or a portion of the security was received as collateral for securities lending. At the end of the period, the value of
	these securities totaled $608,824 or 0.20% of net assets.
^(f)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Consumer, Non-cyclical		23.25	%
Financial		19.80	%
Industrial		17.28	%
Technology		11.16	%
Consumer, Cyclical		10.67	%
Energy		8.51	%
Communications		3.79	%
Utilities		2.78	%
Basic Materials		2.32	%
Money Market Funds		0.59	%
Other Assets and Liabilities		(0.15	)%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		98


		Schedule of Investments
		Principal U.S. Small-Cap ETF
		September 30, 2023 (unaudited)

		June 30, 2023	Purchases			Sales		September 30, 2023
Affiliated Securities		Value		Cost		Proceeds		Value
Principal Government Money
Market Fund — Class R-6 5.26%	$	847,907	$	2,323,217	$	2,562,300	$	608,824
	$	847,907	$	2,323,217	$	2,562,300	$	608,824

					Realized Gain
				Realized		from		Change in
			Gain/(Loss) on		Capital Gain			Unrealized
		Income ^(a)	Investments		Distributions			Gain/(Loss)
Principal Government Money
Market Fund — Class R-6 5.26%	$	—	$	—	$	—	$	—
	$	—	$	—	$	—	$	—

^(a)Amount excludes earnings from securities lending collateral.

See accompanying notes.


	Schedule of Investments
	Principal Value ETF
	September 30, 2023 (unaudited)

COMMON STOCKS — 99.35%		Shares Held		Value
Aerospace & Defense — 1.65%
L3Harris Technologies, Inc.		1,521	$	264,836
Lockheed Martin Corp.		786		321,443
			$	586,279

Agriculture — 1.65%
Altria Group, Inc.		7,604		319,748
Archer-Daniels-Midland Co.		3,499		263,895
			$	583,643

Apparel — 0.60%
Tapestry, Inc.		7,363		211,686
Auto Manufacturers — 0.83%
PACCAR, Inc.		3,441		292,554
Banks — 9.44%
Bank of America Corp.		15,066		412,507
Bank of New York Mellon Corp.		6,161		262,767
Citizens Financial Group, Inc.		8,639		231,525
Comerica, Inc.		4,937		205,132
Fifth Third Bancorp		9,693		245,524
KeyCorp		22,602		243,197
M&T Bank Corp.		2,010		254,164
Northern Trust Corp.		3,344		232,341
PNC Financial Services Group, Inc.		2,328		285,809
Regions Financial Corp.		13,085		225,062
State Street Corp.		3,733		249,962
Truist Financial Corp.		9,226		263,956
Zions Bancorp NA		6,689		233,379
			$	3,345,325

Building Materials — 1.42%
Johnson Controls International PLC		4,905		260,995
Masco Corp.		4,497		240,365
			$	501,360

Chemicals — 2.66%
CF Industries Holdings, Inc.		3,331		285,600
Linde PLC		1,155		430,064
Mosaic Co.		6,339		225,669
			$	941,333

Commercial Services — 1.66%
Automatic Data Processing, Inc.		1,417		340,902
Robert Half, Inc.		3,394		248,712
			$	589,614

Computers — 6.79%
Accenture PLC, Class A		1,458		447,766
Apple, Inc.		8,545		1,462,990
Cognizant Technology Solutions Corp., Class A		4,081		276,447
HP, Inc.		8,509		218,681
			$	2,405,884

Distribution/Wholesale — 0.71%
Pool Corp.		707		251,763

See accompanying notes.

100


Schedule of Investments
Principal Value ETF
September 30, 2023 (unaudited)

COMMON STOCKS (continued)	Shares Held		Value

Diversified Financial Services — 4.31%
Ameriprise Financial, Inc.	831	$	273,964
Discover Financial Services	2,671		231,389
Franklin Resources, Inc.	9,261		227,635
Intercontinental Exchange, Inc.	2,791		307,066
Nasdaq, Inc.	5,253		255,243
Synchrony Financial	7,631		233,280
		$	1,528,577

Electronics — 0.69%
Allegion PLC	2,336		243,411

Environmental Control — 0.76%
Republic Services, Inc.	1,902		271,054

Food — 2.83%
Conagra Brands, Inc.	8,486		232,686
General Mills, Inc.	4,036		258,264
Hershey Co.	1,269		253,902
Kroger Co.	5,766		258,028
		$	1,002,880

Hand/Machine Tools — 0.70%
Snap-on, Inc.	978		249,449

Healthcare — Products — 1.78%
Abbott Laboratories	4,153		402,218
DENTSPLY SIRONA, Inc.	6,666		227,711
		$	629,929

Healthcare — Services — 0.68%
Quest Diagnostics, Inc.	1,967		239,699

Home Builders — 0.68%
PulteGroup, Inc.	3,248		240,514

Household Products/Wares — 0.74%
Avery Dennison Corp.	1,434		261,949

Insurance — 6.67%
Allstate Corp.	2,559		285,098
American International Group, Inc.	4,861		294,577
Chubb Ltd.	1,675		348,702
Cincinnati Financial Corp.	2,487		254,395
Hartford Financial Services Group, Inc.	3,713		263,289
Marsh & McLennan Cos., Inc.	1,821		346,536
MetLife, Inc.	4,578		288,002
Travelers Cos., Inc.	1,732		282,853
		$	2,363,452

Internet — 0.30%
Amazon.com, Inc. ^(a)	848		107,798

Iron & Steel — 0.79%
Steel Dynamics, Inc.	2,609		279,737

Machinery — Construction & Mining — 1.09%
Caterpillar, Inc.	1,410		384,930

Media — 2.51%
Comcast Corp., Class A	9,683		429,344
Fox Corp., Class A	7,509		234,281

See accompanying notes.

101


	Schedule of Investments
	Principal Value ETF
	September 30, 2023 (unaudited)

COMMON STOCKS (continued)		Shares Held		Value

Media (continued)
Fox Corp., Class B		7,855	$	226,852
			$	890,477

Miscellaneous Manufacturers — 1.48%
A O Smith Corp.		3,634		240,316
Parker-Hannifin Corp.		730		284,350
			$	524,666

Oil & Gas — 9.34%
APA Corp.		5,888		241,997
Chevron Corp.		3,331		561,673
Devon Energy Corp.		5,609		267,549
EQT Corp.		6,179		250,744
Exxon Mobil Corp.		6,328		744,046
Marathon Petroleum Corp.		2,123		321,295
Phillips 66		2,608		313,351
Pioneer Natural Resources Co.		1,308		300,252
Valero Energy Corp.		2,190		310,345
			$	3,311,252

Packaging & Containers — 1.53%
Packaging Corp. of America		1,739		267,023
Westrock Co.		7,657		274,121
			$	541,144

Pharmaceuticals — 3.89%
Bristol-Myers Squibb Co.		6,247		362,576
Cencora, Inc.		1,499		269,775
CVS Health Corp.		4,629		323,197
Pfizer, Inc.		12,700		421,259
			$	1,376,807

Pipelines — 0.79%
Williams Cos., Inc.		8,299		279,593

REITs — 7.84%
Alexandria Real Estate Equities, Inc.		2,208		221,021
Essex Property Trust, Inc.		1,086		230,330
Extra Space Storage, Inc.		2,122		257,993
Host Hotels & Resorts, Inc.		16,087		258,518
Invitation Homes, Inc.		7,799		247,150
Kimco Realty Corp.		12,917		227,210
Mid-America Apartment Communities, Inc.		1,852		238,260
Prologis, Inc.		2,979		334,273
Simon Property Group, Inc.		2,435		263,053
UDR, Inc.		6,619		236,100
VICI Properties, Inc.		9,114		265,217
			$	2,779,125

Retail — 4.58%
Best Buy Co., Inc.		3,353		232,933
Darden Restaurants, Inc.		1,681		240,753
Genuine Parts Co.		1,727		249,344
Home Depot, Inc.		1,783		538,751
Lowe's Cos., Inc.		1,731		359,771
			$	1,621,552

See accompanying notes.

102


		Schedule of Investments
		Principal Value ETF
		September 30, 2023 (unaudited)

COMMON STOCKS (continued)				Shares Held		Value

Semiconductors — 6.26%
Analog Devices, Inc.				1,891	$	331,095
Broadcom, Inc.				724		601,340
Microchip Technology, Inc.				3,610		281,761
QUALCOMM, Inc.				3,331		369,941
Skyworks Solutions, Inc.				2,494		245,883
Texas Instruments, Inc.				2,442		388,302
					$	2,218,322

Software — 5.08%
Fidelity National Information Services, Inc.				5,041		278,616
Microsoft Corp.				3,977		1,255,738
Paychex, Inc.				2,317		267,219
					$	1,801,573

Telecommunications — 0.73%
Corning, Inc.				8,491		258,721
Transportation — 5.89%
CH Robinson Worldwide, Inc.				2,746		236,513
CSX Corp.				10,179		313,004
Expeditors International of Washington, Inc.				2,294		262,961
FedEx Corp.				1,186		314,195
Norfolk Southern Corp.				1,387		273,142
Union Pacific Corp.				1,716		349,429
United Parcel Service, Inc., Class B				2,163		337,147
					$	2,086,391
TOTAL COMMON STOCKS					$	35,202,443
INVESTMENT COMPANIES — 0.48%				Shares Held		Value

Money Market Fund — 0.48%
State Street Institutional U.S. Government Money Market Fund — Premier Class
5.30% ^(b)				172,000	$	172,000
TOTAL INVESTMENT COMPANIES					$	172,000
Total Investments					$	35,374,443
Other Assets and Liabilities — 0.17%						59,902
Total Net Assets — 100.00%					$	35,434,345

^(a)	Non-income producing security.
^(b)	1-day yield shown as of period end.

	Portfolio Summary
Sector		Percent
Financial		28.27	%
Technology		18.13	%
Industrial		15.21	%
Consumer, Non-cyclical		13.22	%
Energy		10.13	%
Consumer, Cyclical		7.39	%
Communications		3.55	%
Basic Materials		3.45	%
Money Market Fund		0.48	%
Other Assets and Liabilities		0.17	%
TOTAL NET ASSETS		100.00	%




See accompanying notes.		103

Principal Exchange-Traded Funds
September 30, 2023 (unaudited)

1. Security Valuation

The Funds may invest in series of Principal Funds, Inc. and other investment funds, which may include money market funds and other registered open-end investment companies. Investments in registered open-end investment companies are valued at the respective fund’s closing net asset value (“NAV”) per share on the day of valuation.

The Funds value securities for which market quotations are readily available at fair value, which is determined using the last reported sale price. If no sales are reported, as is regularly the case for some securities traded over-the-counter (“OTC”), securities are valued using the last reported bid price or an evaluated bid price provided by a pricing service.

Pricing services use modeling techniques that incorporate security characteristics such as current quotations by broker/dealers, coupon, maturity, quality, type of issue, trading characteristics, other yield and risk factors and other market conditions to determine an evaluated bid price. When reliable market quotations are not considered to be readily available, which may be the case, for example, with respect to restricted securities, certain debt securities, preferred stocks, and foreign securities, the investments are valued at their fair value as determined in good faith by the Principal Global Investors, LLC (“the Advisor”) under procedures established and periodically reviewed by the Board of Trustees.

The value of foreign securities used in computing the NAV per share is generally determined as of the close of the foreign exchange where the security is principally traded. Events that occur after the close of the applicable foreign market or exchange but prior to the calculation of the Fund’s NAV are reflected in the Fund’s NAV and these securities are valued at fair value. Many factors, provided by independent pricing services, are reviewed in the course of making a good faith determination of a security’s fair value including, but not limited to, price movements in American Depository Receipts (“ADRs”), futures contracts, industry indices, general indices, and foreign currencies.

To the extent the Funds invest in foreign securities listed on foreign exchanges which trade on days on which the Funds do not determine NAV, for example, weekends and other customary national U.S. holidays, the Fund’s NAV could be significantly affected on days when shares are not able to be issued or redeemed by Authorized Participants (“APs”).

Certain securities issued by companies in emerging market countries may have more than one quoted valuation at any given point in time, sometimes referred to as a “local” price and a “premium” price. The premium price is often a negotiated price, which may not consistently represent a price at which a specific transaction can be effected. It is the policy of the Funds to value such securities at prices at which it is expected those shares may be sold, and the Advisor, or any sub-advisor, is authorized to make such determinations subject to such oversight by the Board of Trustees, as may occasionally be necessary.

2. Fair Valuation

Fair value is defined as the price that the Funds would receive upon selling a security or transferring a liability in a timely transaction to an independent buyer in the principal or most advantageous market of the security at the measurement date. In determining fair value, the Funds may use one or more of the following approaches: market, income and/or cost. A hierarchy for inputs is used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available.

Observable inputs are inputs that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from sources independent of the Funds. Unobservable inputs are inputs that reflect the Fund’s own estimates about the estimates market participants would use in pricing the asset or liability developed based on the best information available in the circumstances.

The three-tier hierarchy of inputs is summarized in the three broad levels listed below.

Level 1 — Quoted prices are available in active markets for identical securities as of the reporting date. Investments which are generally included in this category include listed equities and listed derivatives.

Level 2 — Other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.). Investments which are generally included in this category include certain corporate bonds, senior floating rate interests, OTC derivatives, mortgage-backed securities and municipal bonds.

104

Principal Exchange-Traded Funds
September 30, 2023 (unaudited) (continued)

2. Fair Valuation (continued)

Level 3 — Significant unobservable inputs (including the Funds’ assumptions in determining the fair value of investments). Investments which are generally included in this category include certain corporate bonds and certain common stocks.

The availability of observable inputs can vary from security to security and is affected by a wide variety of factors, including, for example, the type of security, whether the security is new and not yet established in the market place, and other characteristics particular to the transaction. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Funds in determining fair value is greatest for instruments categorized in Level 3.

In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, for disclosure purposes, the level in the fair value hierarchy within which the fair value measurement in its entirety falls is determined based on the lowest level input that is significant to the fair value measurement in its entirety.

Fair value is a market based measure considered from the perspective of a market participant who holds the asset rather than an entity specific measure. Therefore, even when market assumptions are not readily available, the Funds’ own assumptions are set to reflect those that market participants would use in pricing the asset or liability at the measurement date. The Funds use prices and inputs that are current as of the measurement date, to the extent available.

Investments which are included in the Level 3 category may be valued using quoted prices from brokers and dealers participating in the market for these investments. These investments are classified as Level 3 investments due to the lack of market transparency and market corroboration to support these quoted prices.

Valuation models may be used as the pricing source for other investments classified as Level 3. Valuation models rely on one or more significant unobservable inputs such as prepayment rates, probability of default, or loss severity in the event of default. Significant increases in any of those inputs in isolation would result in a significantly lower fair value measurement.

The fair values of these entities are dependent on economic, political and other considerations. The values of the underlying investee entities may be affected by significant changes in the economic conditions, changes in government policies, and other factors (e.g., natural disasters, pandemics, accidents, conflicts, etc.).

The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those instruments.

During the period there were no significant purchases, sales, or transfers into or out of Level 3.

The following is a summary of the inputs used as of September 30, 2023, in valuing the Funds' securities carried at fair value:


				Level 2 —
				Other		Level 3 —
		Level 1 —		Significant		Significant
		Quoted		Observable		Unobservable
Fund		Prices		Inputs		Inputs		Totals (Level 1,2,3)

Principal Active High Yield ETF
Bonds*	$	— $		95,898,200	$		— $	95,898,200
Senior Floating Rate Interests*		—		7,573,440			—	7,573,440
U.S. Government & Government Agency
Obligations*		—		1,508,988			—	1,508,988
Investment Companies		4,544,960		—			—	4,544,960
Total investments in securities	$	4,544,960	$	104,980,628	$		— $	109,525,588

105


Principal Exchange-Traded Funds

September 30, 2023 (unaudited) (continued)



2. Fair Valuation (continued)


				Level 2 —
				Other		Level 3 —
		Level 1 —		Significant		Significant
		Quoted		Observable		Unobservable
Fund		Prices		Inputs		Inputs		Totals (Level 1,2,3)

Principal Focused Blue Chip ETF
Common Stocks*	$	6,841,926	$	— $		— $		6,841,926
Investment Companies		10,641		—		—		10,641
Total investments in securities	$	6,852,567	$	— $		— $		6,852,567

Principal Healthcare Innovators ETF
Common Stocks*
Basic Materials	$	26,182	$	— $		— $		26,182
Consumer, Non-cyclical		44,825,953		—		3,797		44,829,750
Industrial		99,055		—		—		99,055
Technology		82,546		—		—		82,546
Investment Companies		1,196,003		—		—		1,196,003
Total investments in securities	$	46,229,739	$	— $		3,797	$	46,233,536

Principal International Adaptive Multi-Factor ETF
Common Stocks*
Basic Materials	$	944,188	$	— $		— $		944,188
Communications		867,705		—		—		867,705
Consumer, Cyclical		2,185,400		—		—		2,185,400
Consumer, Non-cyclical		3,251,561		—		—		3,251,561
Diversified		31,277		—		—		31,277
Energy		1,046,578		—		—		1,046,578
Financial		3,042,762		—		—		3,042,762
Industrial		1,857,072		—		—		1,857,072
Technology		918,952		—		—		918,952
Utilities		494,276		—		—		494,276
Preferred Stocks*		59,939		—		—		59,939
Investment Companies		132,644		—		—		132,644
Total investments in securities	$	14,832,354	$	— $		— $		14,832,354

Principal Investment Grade Corporate Active ETF
Bonds*	$	— $		57,874,615	$	— $		57,874,615
U.S. Government & Government Agency
Obligations*		—		5,847,893		—		5,847,893
Investment Companies		1,425,588		—		—		1,425,588
Total investments in securities	$	1,425,588	$	63,722,508	$	— $		65,148,096
Derivative Assets
Interest rate contracts
Futures	$	44,503	$	— $		— $		44,503
Derivative Liabilities
Interest rate contracts
Futures	$	(91,832	) $	— $		— $		(91,832	)

Principal Millennial Global Growth ETF
Common Stocks*	$	29,670,046	$	— $		— $		29,670,046
Investment Companies		146,654		—		—		146,654
Total investments in securities	$	29,816,700	$	— $		— $		29,816,700

Principal Quality ETF
Common Stocks*	$	38,034,830	$	— $		— $		38,034,830
Investment Companies		143,805		—		—		143,805
Total investments in securities	$	38,178,635	$	— $		— $		38,178,635

Principal Real Estate Active Opportunities ETF
Common Stocks*	$	4,907,583	$	— $		— $		4,907,583
Investment Companies		120,917		—		—		120,917
Total investments in securities	$	5,028,500	$	— $		— $		5,028,500

Principal Spectrum Preferred Securities Active ETF
Bonds*	$	— $		580,131,073	$	— $		580,131,073
Investment Companies		11,451,761		—		—		11,451,761
Total investments in securities	$	11,451,761	$	580,131,073	$	— $		591,582,834

106


Principal Exchange-Traded Funds
September 30, 2023 (unaudited) (continued)



2. Fair Valuation (continued)


				Level 2 —
				Other		Level 3 —
		Level 1 —		Significant		Significant
		Quoted		Observable		Unobservable
Fund		Prices		Inputs		Inputs		Totals (Level 1,2,3)

Principal Spectrum Tax-Advantaged Dividend Active ETF
Preferred Stocks*	$	2,047,465	$	— $		— $		2,047,465
Bonds*		—		17,580,848		—		17,580,848
Investment Companies		187,272		—		—		187,272
Total investments in securities	$	2,234,737	$	17,580,848	$	— $		19,815,585

Principal U.S. Large-Cap Adaptive Multi-Factor ETF
Common Stocks*	$	6,318,872	$	— $		— $		6,318,872
Investment Companies		29,607		—		—		29,607
Total investments in securities	$	6,348,479	$	— $		— $		6,348,479

Principal U.S. Mega-Cap ETF
Common Stocks*	$	1,456,590,999	$	— $		— $		1,456,590,999
Investment Companies		6,076,360		—		—		6,076,360
Total investments in securities	$	1,462,667,359	$	— $		— $		1,462,667,359

Principal U.S. Small-Cap Adaptive Multi-Factor ETF
Common Stocks*	$	5,630,072	$	— $		— $		5,630,072
Investment Companies		23,890		—		—		23,890
Total investments in securities	$	5,653,962	$	— $		— $		5,653,962

Principal U.S. Small-Cap ETF
Common Stocks*
Basic Materials	$	6,965,088	$	— $		— $		6,965,088
Communications		11,394,685		—		—		11,394,685
Consumer, Cyclical		32,074,023		—		—		32,074,023
Consumer, Non-cyclical		69,867,343		—		3,863		69,871,206
Energy		25,597,408		—		—		25,597,408
Financial		59,515,531		—		—		59,515,531
Industrial		51,927,386		—		—		51,927,386
Technology		33,537,446		—		—		33,537,446
Utilities		8,348,816		—		—		8,348,816
Investment Companies		1,779,001		—		—		1,779,001
Total investments in securities	$	301,006,727	$	— $		3,863	$	301,010,590

Principal Value ETF
Common Stocks*	$	35,202,443	$	— $		— $		35,202,443
Investment Companies		172,000		—		—		172,000
Total investments in securities	$	35,374,443	$	— $		— $		35,374,443

* For additional detail regarding sector and/or sub-industry classifications, please see the Schedules of Investments.

The Funds’ Schedules of Investments for the period ended September 30, 2023 has not been audited. This report is provided for the general information of the Funds’ shareholders. For more information regarding the Funds and their holdings, please see the Funds’ prospectus.

107