Year	US Dollars adjusted for inflation)
1960	17735.53884
1961	18675.94371
1962	19610.03485
1963	20609.97087
1964	21690.11607
1965	22864.46394
1966	23863.23561
1967	25083.7502
1968	26164.4717
1969	27538.63563
1970	25199.42138
1971	24945.13535
1972	23534.51912
1973	24806.51609
1974	20247.51814
1975	16904.75788
1976	17410.7457
1977	18598.8715
1978	20772.205
1979	25627.21381
1980	26692.07256
1981	23696.72559
1982	24724.11167
1983	25054.74505
1984	28004.86701
1985	28772.84651
1986	28745.57251
1987	29085.10964
1988	29253.76904
1989	30692.41389
1990	29673.81103
1991	27912.42205
1992	26338.44977
1993	25929.35258
1994	26287.30994
1995	27021.62398
1996	27801.66246
1997	28060.56751
1998	29071.01194
1999	30775.25652
2000	31587.59103
2001	31856.08584
2002	32080.35346
2003	31013.63921
2004	30629.72917
2005	31023.04722
2006	31180.61512
2007	31031.231
2008	29758.2498
2009	28019.14864
2010	27979.11493
2011	27710.10196
2012	28145.35866
2013	27643.39521
2014	27246.48486
2015	27198.9076
2016	26439.05364
2017	26538.94563