Year	constant 2015 US$
1970	15654.345141308118
1971	16324.7898397354
1972	16897.666718127348
1973	17805.091467385562
1974	17789.763130060233
1975	17631.45430069135
1976	18227.833328003828
1977	18638.52432746512
1978	19623.490539521732
1979	20156.47824339888
1980	19971.110276610565
1981	19750.764736497636
1982	20009.03531171473
1983	20127.204277116045
1984	20219.293867353987
1985	20608.895187103666
1986	21594.41579737807
1987	22090.203862996113
1988	23114.272088986898
1989	23822.39590856946
1990	24364.367871145943
1991	24177.005059017298
1992	24523.383686425288
1993	24308.35743311132
1994	24759.036176652193
1995	25196.427041231524
1996	25558.2493948364
1997	26209.148033042897
1998	27238.150642810666
1999	28238.78884216488
2000	28753.271760654683
2001	29140.565634605256
2002	29046.164370469287
2003	29100.320882820175
2004	29636.943733719552
2005	29821.713041488027
2006	30216.728728306964
2007	30820.793229843766
2008	30523.83882778946
2009	29504.897305675935
2010	29860.97898251939
2011	30234.412072448536
2012	29918.865026811978
2013	30066.780586830693
2014	30304.691694771507
2015	30908.686330464898
2016	31213.79647363831
2017	31720.268128974407
2018	32035.541171206078
2019	32441.654431947896
2020	29217.861226016103
2021	31764.13053734862