[8] Cost of sales and other functional costs

The total cost of materials recognized under functional costs in the consolidated income statement went up by €630.4 million to €5,717.5 million in 2022 (2021: €5,087.1 million), mainly due to the increase in revenue and higher prices for materials.

The total personnel expenses recognized under functional costs rose by €236.7 million to €2,848.7 million (2021: €2,612.0 million). This rise can be explained by the growth in the average number of employees for the year and general salary increases.

Personnel expenses included wages and salaries of €2,274.9 million (2021: €2,098.2 million), social security contributions of €500.1 million (2021: €453.7 million), and post-employment benefit costs and other benefits of €73.6 million (2021: €60.1 million). Post-employment benefit costs and other benefits comprised a current service cost from defined benefit pension plans of €47.7 million (2021: €57.3 million). The changes to the pension benefit conditions in Germany resulted in unrecognized past service income of €12.3 million in the reporting year (2021: €32.7 million). The interest cost from the unwinding of the discount on estimated pension obligations is not recognized under personnel expenses and is instead reported under financial expenses as a component of interest expense.

Impairment losses and depreciation expenses on property, plant and equipment together with impairment losses and amortization expenses on intangible assets, as well as reversals of impairment losses, were recognized under functional costs in a total amount of €1,033.5 million in the reporting year (2021: €940.9 million).

In 2022, the cost of sales and selling expenses included impairment losses of €10.9 million on inventories and impairment losses of €3.4 million on trade receivables and lease receivables of the Russian subsidiaries in the Industrial Trucks & Services segment that are to be sold. Further information can be found in note [27].