9. Costs of products, goods and materials sold

 noteperiod ended 31/12/2013period ended 31/12/2012
Value of goods and materials sold   511,35 417,861
Expenses by type   2,144,670 2,147,554
Depreciation   51,948 57,406
Material and energy consumption   1,869,551 1,864,654
External services   71,702 73,386
Salaries and employee benefits   98,509 99,796
Social insurance and other benefits   24,103 24,584
Taxes and fees   14,917 15,675
Other   13,94 12,053
Total   2,656,020 2,565,415
Change in inventories and prepayments    3,875 25,093
Cost of products for own needs   8,243 11,199
Effective portion of the settlement of hedging instruments (*) 27 4,836 2,853
Costs of sales    48,868 45,053
General administration costs   64,99 67,196
Costs of products, goods and materials sold   2,534,880 2,414,021

(*) Refers to the hedging of future cash flows associated with the purchase of raw materials for production.