Year	current US$
1990	6048210.11448024
1991	7201597.44183495
1992	7533893.95250414
1993	7339611.70210134
1994	8218517.48612668
1995	8764536.72347224
1996	9305759.39435183
1997	9438597.33481471
1998	9346268.45765214
1999	9752451.14796166
2000	9371647.11059542
2001	9339349.27277862
2002	9596919.5018143
2003	10578047.9580663
2004	11621479.5347906
2005	11956801.5644106
2006	12456852.107453
2007	14566725.6490101
2008	16065354.844998
2009	15808717.9450256
2010	17887860.0911281
2011	20106510.1769501
2012	19811599.2267811
2013	20335106.3779395
2014	20481348.0381088
2015	19538044.7498137
2016	20206747.2578932
2017	21618329.9184862
2018	22171173.6602317
2019	22332944.3616142
2020	22741843.5722521