Year	current US$
1972	1990339.5307841
1973	2370915.73708359
1974	3790175.84591633
1979	2220467.81956474
1980	2861950.03912896
1981	2869475.10958701
1982	3327986.19100217
1983	2738472.13489215
1984	2838887.67206054
1985	2432755.88930927
1986	2582855.24778432
1987	2692850.74827989
1988	3321440.77675174
1989	3329013.3136424
1990	3391351.89539597
1991	4007827.81234946
1992	3101728.94183954
1993	3184489.47158296
1994	3940104.41114331
1995	4130404.30816592
1996	4879700.65376569
1997	5070515.72323672
1998	5045992.69257078
1999	5429446.1009251
2000	5665004.71604645
2001	5147443.15806713
2002	5543960.13895712
2003	7224573.23985318
2004	7737416.01825833
2005	9301959.22213933
2006	8248879.76936501
2007	9806527.60492416
2008	9592109.52420541
2009	9426198.38846824
2010	12520164.2320968
2011	14232828.3070797
2012	15125571.4087046
2013	15330555.5023049
2014	14448189.5957212
2015	13411421.2486285
2016	13584270.0849379
2017	13569487.8466151
2018	14484233.9965061
2019	13307583.9172998
2020	14667807.4581484
2021	16272097.1394554