Year	US Dollars adjusted for inflation)
1991	3509.413
1992	3737.963
1993	3899.925
1994	4002.525
1995	4270.44
1996	4312.312
1997	4474.58
1998	4277.647
1999	4511.97
2000	4743.733
2001	4632.83
2002	4815.555
2003	5026.053
2004	5265.316
2005	5510.399
2006	5824.378
2007	6153.237
2008	6439.26
2009	6687.069
2010	7239.879
2011	7772.311
2012	8544.145
2013	8568.574
2014	9081.831
2015	9516.688
2016	9845.688
2017	10263.871
2018	10758.945
2019	11301.217
2020	11895.314
2021	12534.841
2022	13222.05