On January 1, 2017 Ohio Corporation (a calendar-year corporation) bought a machine for $25,000 cash. The estimated useful life was four years, and the residual value was $3,000. Assume that the estimated useful life in units is 100,000 units. Units produced were 30,000 in 2017 and 14,000 in 2018.

Calculate depreciation expense, accumulated depreciation, and book value for 2017 and 2018 under the straight-line, units-of-production, and double-declining balance methods.