Year	current US$
1996	3804461657.93091
1997	4277907793.57633
1998	4832348341.95887
1999	5384824841.14242
2000	5969084203.15924
2001	6205672515.15067
2002	6791702258.37291
2003	6568422591.43518
2004	6342186578.97647
2005	7054492779.07283
2006	7898313860.10128
2007	9354047506.0216
2008	7472335050.51579
2009	8782169598.07242
2010	25234752661.6572
2011	30806717492.558
2012	37102766294.1605
2013	39788237264.2068
2014	44691684169.966
2015	35773028905.2199
2016	40433261670.2906
2017	46405840148.3482
2018	55342990288.8287
2019	58982601408.6869
2020	67062482948.2784
2021	67279083395.8985