Year	US Dollars adjusted for inflation)
1991	21669.447
1992	19366.002
1993	18079.412
1994	19707.627
1995	21252.049
1996	22550.229
1997	24377.012
1998	25596.355
1999	26309.023
2000	28378.066
2001	29527.438
2002	31331.693
2003	32493.715
2004	32880.887
2005	33914.156
2006	35274.09
2007	36369.84
2008	36551.387
2009	34219.055
2010	35016.879
2011	36436
2012	37011.926
2013	37660.512
2014	36477.727
2015	36408.254
2016	37276.941
2017	37788.211
2018	38127.102
2019	38995.332
2020	40060.699
2021	41131.191
2022	42244.516