Calvin purchased a new office desk on july 23, 2018, at a cost of $2,373. he did not claim the bonus depreciation deduction. using the half-year convention, calvin may claim 2018 depreciation in the amount of calvin purchased a new office desk on july 23, 2018, at a cost of $2,373. he did not claim the bonus depreciation deduction. using the half-year convention, calvin may claim 2018 depreciation in the amount of ?