Year	current US$
1970	254385.808615449
1971	649802.431610942
1972	362343.335530653
1973	492058.878513357
1974	624300.696942098
1975	1384023.15376984
1976	700054.154528986
1977	1286896.89527268
1978	1302842.6527789
1979	1745345.33155108
1980	1833367.83940741
1981	1434739.93012133
1982	1970868.11161437
1983	1723755.19379739
1984	1420771.29516226
1985	1216989.94806169
1986	1785787.87656068
1987	1872490.87146647
1988	1865880.74646157
1989	1984508.88512627
1990	1948192.18454417
1991	2519068.3201801
1992	2219064.29484345
1993	2874437.06064712
1994	1140872.24330926
1995	1905260.23340232
1996	2319741.70337249
1997	3201048.76847291
1998	4138280.53673442
1999	5594639.15998936
2000	2586304.37712534
2001	3911171.89701658
2002	3722784.08523909
2003	3939991.70850621
2004	2793259.3644961
2005	2766738.59744703
2006	3499902.87041494
2007	3506661.92887157
2008	6261997.72269039
2009	6322792.04440282
2010	7768397.97559081
2011	7961444.12758194
2012	9005134.97797412
2013	8536724.08136894
2014	10670157.970641
2015	8957639.78298561
2016	6214540.64495993
2017	8861558.7405593
2018	7711678.24928235
2019	9348577.97662164
2020	7034963.73196322
2021	6727861.37784991