federal realty investment trust schedule iii summary of real estate and accumulated depreciation - continued three years ended december 31 , 2011 reconciliation of accumulated depreciation and amortization ( in thousands ) balance , december 31 , 2008................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2009................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2010................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2011................................................................................................................................... . $ 846258 103698 ( 11869 ) 938087 108261 ( 11144 ) 1035204 114180 ( 21796 ) $ 1127588 .

Table: balance december 31 2008 $ 846258 additions during period 2014depreciation and amortization expense 103698 deductions during period 2014disposition and retirements of property -11869 ( 11869 ) balance december 31 2009 938087 additions during period 2014depreciation and amortization expense 108261 deductions during period 2014disposition and retirements of property -11144 ( 11144 ) balance december 31 2010 1035204 additions during period 2014depreciation and amortization expense 114180 deductions during period 2014disposition and retirements of property -21796 ( 21796 ) balance december 31 2011 $ 1127588

federal realty investment trust schedule iii summary of real estate and accumulated depreciation - continued three years ended december 31 , 2011 reconciliation of accumulated depreciation and amortization ( in thousands ) balance , december 31 , 2008................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2009................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2010................................................................................................................................... . additions during period 2014depreciation and amortization expense .................................................................... . deductions during period 2014disposition and retirements of property ................................................................. . balance , december 31 , 2011................................................................................................................................... . $ 846258 103698 ( 11869 ) 938087 108261 ( 11144 ) 1035204 114180 ( 21796 ) $ 1127588 .

Question: considering the years 2008-2010 , what is the value of the average deductions?\\n
Answer: 14936.33
Calculation: divide(add(add(11869, 11144), 21796), const_3)
Explanation: it is the sum of all deductions divided by the sum of the years .