Year	current US$
1981	23995454.55
1982	17824171.86
1983	31156472.25
1984	31617262.05
1985	23510696.96
1986	31480707.77
1987	36225446.68
1988	51995465.3
1989	47975133.13
1990	59471681.31
1991	95028302.57
1992	95686437.01
1993	114367478.8
1994	126773605.5
1995	95428213.38
1996	116187383.9
1997	102018696.19999999
1998	125188985.7
1999	151081048.79999998
2000	56534600
2001	114310161
2002	76766262
2003	69192332
2004	56358178
2005	58369684
2006	64279937.00000001
2007	70290535
2008	104775493
2009	367847066
2010	169849944
2011	217451150
2012	194665209
2013	163323680
2014	169795800
2015	255904318
2016	252732278
2017	268867388
2018	289352398
2019	216297614
2020	246988970