Only the declining balance method and straight line method of computing depreciation are allowed under MACRS. Taxpayers using the declining balance change to the straight line method at the point at which depreciation deductions are optimized. See the tables below. All tangible personal property acquired during the year is considered placed in service in the middle of the tax year ("half-year convention"). Real property is considered placed in service in the middle of the month in which acquired ("mid-month convention"). Special rules apply for pro rating deductions for short tax years and for the first year of business, or where more than 40% of tangible personal property additions are in the final quarter of the year.