Yuan Inc purchased a new machine on January 1, 2011. Relevant information is as follows: Cost when acquired Estimated residual value Estimated useful life $26,000 2,000 10 years It is now the beginning of year 6 and the management reevaluated the estimates related to the machine. Compute the depreciation expense for year 6 with the information that the estimated total useful life is changed to 15 years; residual value is unchanged. (Fill in number only)