Equipment was acquired on January 1, 2014, at a cost of $90,000. The equipment was originally estimated to have a salvage value of $5,000 and an estimated life of 10 years. Depreciation has been recorded through December 31, 2017, using the straight-line method. On January 1, 2018, the estimated salvage value was revised to $6,000 and the useful life was revised to a total of 8 years. Instructions: Record the depreciation entries for 2018 and 2019.