Arcadia HS, purchased equipment for $510,000 which was estimated to have a useful life of 10 years with a residual value of $10,000 at the end of that time. Depreciation has been recorded for 7 years on a straight-line basis. In 2015 (year 8), it is determined that the total estimated life should be 15 years with a residual value of $5,000 at the end of that time.

Questions:

Does prior years depreciation need to be restated?

Calculate the depreciation expense for 2015.