Year	current US$
1987	11502.632644795465
1988	13825.757575757576
1989	14047.410008779632
1990	7500000000
1991	6400000000
1992	3729999999.9999995
1993	2701301482.701812
1994	2514070771.8027306
1995	2693768412.891793
1996	3095047603.808305
1997	3510520231.2138724
1998	3613497316.5531864
1999	2800025882.7167172
2000	3057475335.1884646
2001	3219462262.007499
2002	3395766677.673153
2003	3991377904.1316156
2004	5125365191.986644
2005	6410912049.871047
2006	7745250733.950674
2007	10172931088.565523
2008	12795145130.910282
2009	10766920065.825115
2010	12426907967.157818
2011	15475290469.286894
2012	16894392033.225578
2013	17517660143.685932
2014	17966015109.304302
2015	15223796148.83962
2016	15444548901.963682
2017	16473125375.068438
2018	17902544880.64707
2019	17638337116.9126
2020	16010869215.679968
2021	18853115588.81058
2022	24984568959.604965
2023	30535530479.022663