Year	US Dollars adjusted for inflation)
1991	6987.48
1992	7489.661
1993	7837.049
1994	7843.132
1995	8063.042
1996	8426.797
1997	8865.722
1998	9261.27
1999	9650.522
2000	9970.148
2001	9923.643
2002	10255.964
2003	10040.894
2004	9954.219
2005	10610.427
2006	11374.443
2007	12031.413
2008	12390.213
2009	12638.721
2010	13108.358
2011	13088.855
2012	13255.29
2013	13710.488
2014	14315.335
2015	14910.442
2016	15857.057
2017	16389.521
2018	16970.189
2019	17560.951
2020	18162.24
2021	18782.568
2022	19353.574