Year	constant 2015 US$
1970	16290.793248047035
1971	16804.541879360513
1972	17814.075790682386
1973	18985.06493946678
1974	19242.618140305844
1975	18957.195552609646
1976	20010.563376509155
1977	20000.707025002066
1978	20553.70858158198
1979	20925.46165712297
1980	20778.326250510563
1981	20234.6709306434
1982	20209.35523894707
1983	20377.770900346204
1984	21026.59219409315
1985	21626.01278842623
1986	22657.50831998489
1987	23356.300775350897
1988	24681.44657583354
1989	25473.567788185355
1990	26113.973843632346
1991	26570.867646377243
1992	27101.489414665935
1993	27182.161887095
1994	28155.643719679298
1995	28544.218872771788
1996	28618.423568860246
1997	29564.12573315922
1998	30092.66189721496
1999	30741.389483005532
2000	31495.00144765555
2001	31387.316047550066
2002	31835.5447623153
2003	31804.767128947766
2004	32418.11488917472
2005	32667.936910764933
2006	33025.61175300859
2007	33956.00672919997
2008	33235.47094431942
2009	32503.768520981524
2010	32663.201303081645
2011	31808.389528908087
2012	32641.36593365709
2013	32815.703031349316
2014	33207.110909927134
2015	33799.739833793734
2016	34180.93784753469
2017	34478.506348582116
2018	34672.775408737245
2019	35508.23605368239
2020	33021.92117839608
2021	34719.680913705204