Tables A-1 and A-2. Summary: These tables are used to determine the percentage rate used in calculating the depreciation of property. Table A-1 is for 3-, 5-, 7-, 10-, 15-, and 20-Year Property using the Half-Year Convention and lists the percentages for years 1 through 21 under each category of recovery period. Table A-2 is for 3-, 5-, 7-, 10-, 15-, and 20-Year Property using Mid-Quarter Convention and Placed in Service in First Quarter and lists the percentages for years 1 through 21 under each category of recovery period.