Depredation by Units-of-activity Method Prior to adjustment at the end of the year, the balance in Trude is $407,400 and the balance in accumsan Details of the subsidiary ledger are as follows: Accumulated Estimated Estimated Depreciation Operated Truck Residual Useful at Beginning During No. Cost Value Lite of Year Year $86,000 $12,900 200,000 miles 30,000 miles 2 110,900 13,308 310,000 $22,180 31,000 3 93,000 13,020 210,000 74,400 21,000 117,500 14,100 330,000 23,500 39,600