Year	US Dollars adjusted for inflation)
1991	5001.167
1992	5086.457
1993	4957.805
1994	4989.452
1995	4985.279
1996	5023.113
1997	5094.683
1998	5208.481
1999	5213.268
2000	5506.597
2001	5671.65
2002	5838.434
2003	5988.894
2004	6138.319
2005	6310.57
2006	6331.763
2007	6349.911
2008	6381.059
2009	6427.426
2010	7005.058
2011	5962.33
2012	5886.213
2013	5989.29
2014	5829.518
2015	4011.726
2016	3473.322
2017	2930.532
2018	2842.883
2019	2751.208
2020	2964.939
2021	3058.205
2022	3156.556