Year	US Dollars adjusted for inflation)
1960	241.18609
1961	253.89834
1962	249.89398
1963	240.83796
1964	241.55146
1965	268.00121
1966	296.24969
1967	310.07477
1968	296.55221
1969	306.02908
1970	299.52855
1971	338.90726
1972	350.32747
1973	348.53782
1974	363.067
1975	374.13363
1976	381.17248
1977	387.6367
1978	412.27568
1979	417.49536
1980	407.17166
1981	375.60706
1982	375.69538
1983	379.31801
1984	386.0562
1985	386.05806
1986	364.3035
1987	347.66513
1988	337.24585
1989	324.57889
1990	330.59112
1991	351.86164
1992	323.09177
1993	353.45571
1994	315.92962
1995	364.60851
1996	383.51789
1997	387.63064
1998	390.58249
1999	390.08937
2000	384.68017
2001	355.55085
2002	352.02845
2003	362.37194
2004	371.78737
2005	373.23212
2006	379.43861
2007	403.4946
2008	421.22614
2009	442.55728
2010	458.86817
2011	466.96334
2012	461.88734
2013	471.84047
2014	484.36862
2015	483.62881
2016	481.45194
2017	486.44533