Riverbed Corp purchased a piece of equipment for $8,000. It estimated a 8 -year life and $2,320 salvage value. At the end of year 4 (before the depreciation adjustment), it estimated the new total life to be 10 years and the new salvage value to be $4,640. Compute the revised depreciation. Company uses straight-line depreciation method. (Round answer to 0 decimal places, es. 125.) Revised depreciation $