Year	current US$
1970	296.1591725341284
1971	310.6100690452019
1972	397.6374645208227
1973	483.7141314877291
1974	639.8837470135813
1975	747.7415277690081
1976	786.344681898857
1977	847.8218012533068
1978	1088.1672553554274
1979	1088.4458954564052
1980	1484.2472268221175
1981	1612.9208816726498
1982	1697.1798276002924
1983	1790.8228667944484
1984	1941.9375893660374
1985	2032.3564609427322
1986	2295.9173297938955
1987	2277.070847120819
1988	1953.9334681575083
1989	1791.8158052048518
1990	1896.7029085451748
1991	1355.5517363086803
1992	1440.1577552040776
1993	1450.0312601418564
1994	1194.7257422061764
1995	1125.2927287659832
1996	1205.716559294711
1997	1254.4264786854003
1998	1289.6823510617494
1999	1224.214309235195
2000	1298.795023997907
2001	1345.104940745217
2002	1351.8682404661376
2003	1571.7244958435617
2004	1889.0614256768663
2005	2099.7720894223903
2006	2357.442054495252
2007	2820.398624238668
2008	3539.0496689545544
2009	2985.068703246363
2010	3483.2360459261267
2011	4120.890186607094
2012	4325.009029971259
2013	4255.886501346715
2014	4214.845236270777
2015	3359.117637262293
2016	3297.7433062190994
2017	3339.934931249187
2018	3216.4348546121837
2019	3140.907178986351
2020	2726.4227472273215
2021	2846.6405075142093