Year	US Dollars adjusted for inflation)
1991	4161.527
1992	4044.069
1993	4010.108
1994	4077.475
1995	4151.868
1996	4287.551
1997	4396.218
1998	4243.665
1999	4267.959
2000	4346.777
2001	4354.73
2002	4404.627
2003	4515.023
2004	4732.501
2005	4840.063
2006	4968.719
2007	5132.973
2008	5229.094
2009	5124.27
2010	5360.293
2011	5376.099
2012	5646.368
2013	5942.85
2014	6120.776
2015	6383.931
2016	6682.813
2017	6986.072
2018	7276.134
2019	7579.067
2020	7877.251
2021	8178.44
2022	8483.376