Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments in the form of commercial paper and corporate bonds, and trade accounts receivable. The Company’s cash and cash equivalents and short- term investments are placed with high-credit-quality financial institutions, and at times exceed federally insured limits. To date, the Company has not experienced any credit loss relating to its cash and cash equivalents or short-term investments.

Significant customers that represent 10% or more of revenue are set forth in the following tables:

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In the three and six months ended June 30, 2023, sales to government entities comprised 75.4% and 78.1% of the Company’s total revenue, respectively. In the three and six months ended June 30, 2022, sales to government entities comprised 67.8% and 72.0% of the Company’s total revenue, respectively.

Significant customers that represent 10% or more of accounts receivable are set forth in the following tables:

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The following table presents a summary of revenue by geography for the three and six months ended June 30, 2023 and June 30, 2022

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Revenues from external customers are attributed to individual countries based on the physical location in which the services are provided or the particular customer location with whom the Company has contracted.