Machinery purchased for $70,200 by Sheffield Co. in 2016 was originally estimated to have a life of 8 years with a salvage value of $4,680 at the end of that time. Depreciation has been entered for 5 years on this basis. In 2021, it is determined that the total estimated life should be 10 years with a salvage value of $5,265 at the end of that time. Assume straight-line depreciation.

Prepare the entry to correct the prior years' depreciation, if necessary.

Prepare an entry to record depreciation for 2021.