Year	US Dollars adjusted for inflation)
1987	4020.58321
1988	4105.52075
1989	4243.77461
1990	3965.38272
1991	3624.29263
1992	3263.37186
1993	2797.56841
1994	2166.69302
1995	1917.45137
1996	1741.08871
1997	1704.31402
1998	1686.94179
1999	1699.51747
2000	1817.9971
2001	2005.31514
2002	2130.65856
2003	2349.93151
2004	2654.33355
2005	2746.0498
2006	2966.50006
2007	3220.01356
2008	3311.95841
2009	2834.34325
2010	2965.14237
2011	3138.46507
2012	3153.73924
2013	3160.08374
2014	3123.91557
2015	2828.88539
2016	2905.85744
2017	2991.62931