Year	current US$
1978	26000000
1979	42000000
1980	56000000
1981	42000000
1982	28000000
1983	28000000
1984	32000000
1985	27000000
1986	32000000
1987	34000000
1988	30280000.69
1989	26559999.47
1990	22840000.15
1991	19120000.84
1992	15399999.62
1993	57700000.76
1994	62400001.53
1995	63600000
1996	65000000
1997	65700000
1998	68500000
1999	64300000
2000	86343658.5898822
2001	189600000
2002	206630000
2003	273420000
2004	311780000
2005	432090000
2006	540635441.916292
2007	606498926.517186
2008	705144403.358363
2009	628542376.088907
2010	644300740.057192
2011	697379575.129916
2012	577532962.100773
2013	535004409.367289
2014	505346891.730357
2015	494433532.139966
2016	391579047.663514
2017	479937459.808431
2018	522441503.008565
2019	561398444.719758
2020	648090050.021815
2021	901123183.017933
2022	1267449071.25346
2023	1600000000