Machinery purchased for $58,240 by Sheffield Co. in 2018 was originally estimated to have a life of 8 years with a residual value of $4,480 at the end of that time. Depreciation has been entered for 5 years on this basis. In 2023, it is determined that the total estimated life should be 10 years with a residual value of $5,040 at the end of that time. Assume straight-line depreciation.