Year	US Dollars adjusted for inflation)
1991	10716.541
1992	10143.674
1993	9204.051
1994	8603.217
1995	8233.298
1996	8531.461
1997	8775.495
1998	8699.508
1999	9040.134
2000	9893.604
2001	10905.865
2002	11721.924
2003	12592.756
2004	13625.381
2005	14613.703
2006	15868.649
2007	16909.314
2008	17063.498
2009	17124.945
2010	17933.293
2011	18980.43
2012	19645.977
2013	20583.201
2014	21176.354
2015	21255.904
2016	21348.305
2017	21897.027
2018	22510.258
2019	23161.41
2020	23991.748
2021	25091.139
2022	26414.104