Year	US Dollars adjusted for inflation)
1960	601.85281
1961	621.04237
1962	587.43956
1963	572.5818
1964	573.37381
1965	567.46241
1966	559.56508
1967	573.56037
1968	569.44008
1969	597.27471
1970	599.01272
1971	594.12292
1972	582.95053
1973	582.76147
1974	607.56936
1975	597.37468
1976	616.07477
1977	624.96301
1978	617.36962
1979	586.86299
1980	545.51989
1981	521.76621
1982	545.28426
1983	486.04359
1984	517.0581
1985	523.40509
1986	529.51876
1987	492.72179
1988	490.99062
1989	490.16708
1990	468.69092
1991	454.52932
1992	414.17635
1993	404.40717
1994	412.99986
1995	431.4989
1996	404.22517
1997	415.78753
1998	425.63991
1999	431.47277
2000	411.93839
2001	421.65942
2002	428.47746
2003	397.81154
2004	414.03045
2005	410.41506
2006	422.43891
2007	434.2507
2008	436.07395
2009	437.60162
2010	446.44369
2011	458.33302
2012	475.66764
2013	300.47974
2014	302.54653
2015	314.92669
2016	325.72047
2017	335.02609