Year	US Dollars adjusted for inflation)
1970	2404.55747
1971	2311.24044
1972	2551.23849
1973	3039.81354
1974	4353.90336
1975	4520.99902
1976	3263.01764
1977	3066.86831
1978	3053.56917
1979	2660.8662
1980	2190.43049
1981	2090.0531
1982	2204.116
1983	2156.46531
1984	2224.89822
1985	2030.81035
1986	1967.45562
1987	1740.79451
1988	1849.97481
1989	1743.33569
1990	1691.1364
1991	1661.58167
1992	1652.19231
1993	1645.64991
1994	1653.23735
1995	1630.71351
1996	1633.61625
1997	1634.39281
1998	1712.39408
1999	1657.27335
2000	1730.81208
2001	1676.51854
2002	1710.43241
2003	1714.28801
2004	1655.6805
2005	1704.10557
2006	1642.73429
2007	1643.15674
2008	1577.91979
2009	1549.00463
2010	1493.16051
2011	1471.55249
2012	1519.48036
2013	1578.87555
2014	1565.24254
2015	1696.46677
2016	1685.99267
2017	1708.39266