Year	US Dollars adjusted for inflation)
1991	22431.582
1992	21744.332
1993	22852.715
1994	23870.412
1995	24452.602
1996	25027.086
1997	26006.338
1998	26733.879
1999	26523.014
2000	27393.295
2001	28258.609
2002	29483.926
2003	30144.09
2004	31826.125
2005	33173.488
2006	34364.188
2007	34684.566
2008	35436.562
2009	33983.656
2010	34351.809
2011	34767.281
2012	33708.91
2013	33860.043
2014	33358.551
2015	33421.48
2016	32971.145
2017	34188.785
2018	35557.398
2019	36579.902
2020	37533.676
2021	38509.945
2022	39564.328