On January 1, 2012, Knapp Corporation acquired machinery at a cost of $750,000. Knapp adopted the straight-line method of depreciation for this machinery and had been recording depreciation over an estimated useful life of ten years, with a $50,000 residual value. At the beginning of 2015, a decision was made to change initial estimated useful life to 13 years, with a $40,000 residual value. The depreciation expense for 2015 would be