| Schedule of administrative expenses |
| | | | | | | | | 2023 | | 2022 | | 2021 | | | $’000 | | $'000 | | $'000 | | | | | | | | Staff costs (note 8.3) | | 156,602 | | 132,399 | | 101,567 | Professional fees | | 61,094 | | 38,964 | | 49,685 | Impairment of withholding tax receivables* | | 47,992 | | 52,334 | | 61,810 | Facilities, short-term rental and upkeep | | 43,616 | | 34,203 | | 23,210 | Key management compensation (note 30.2) | | 18,508 | | 21,703 | | 25,642 | Travel costs | | 14,124 | | 15,535 | | 8,654 | Share-based payment expense (note 28) | | 13,370 | | 13,265 | | 11,780 | Depreciation (note 14) | | 11,314 | | 9,995 | | 13,917 | Amortization (note 15) | | 5,765 | | 5,280 | | 4,115 | Business combination transaction costs | | 2,432 | | 20,851 | | 15,779 | Impairment of goodwill | | — | | 121,596 | | — | Operating taxes | | (1,005) | | 963 | | 1,561 | Net (gain)/loss on disposal of property, plant and equipment | | (3,806) | | 3,382 | | (2,499) | Other | | 34,777 | | 30,705 | | 21,290 | | | 404,783 | | 501,175 | | 336,511 |
*Withholding tax receivables were impaired following the Group’s assessment of the recoverability of withholding tax assets based on a five year cash flow projection and an analysis of the utilization of withholding tax balances against future income tax liabilities. | | | | | | | | | 2023 | | 2022 | | 2021 | | | $’000 | | $'000 | | $'000 | | | | | | | | Salaries and wages | | 157,807 | | 137,450 | | 106,754 | Other benefits | | 19,877 | | 18,768 | | 16,282 | Share-based payment expense (note 28) | | 13,370 | | 13,265 | | 11,780 | Pension contribution – employer | | 12,067 | | 9,410 | | 4,854 | | | 203,121 | | 178,893 | | 139,670 |
| | | | | | | | | 2023 | | 2022 | | 2021 | | | $’000 | | $'000 | | $'000 | | | | | | | | Administrative expenses | | 169,972 | | 145,664 | | 113,347 | Cost of sales | | 33,149 | | 33,229 | | 26,323 | | | 203,121 | | 178,893 | | 139,670 |
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