On January 1, 2016, Poultry Processing Company purchased a freezer and related installation equipment for $42,000. The equipment had a three-year estimated life with a $3,000 salvage value. Straight-line depreciation was used. At the beginning of 2018, Poultry Processing revised the expected life of the asset to four years rather than three years. The salvage value was revised to $2,000.
Compute the depreciation expense for each of the four years, 2016–2019.