Year	US Dollars
1960	15.72179
1961	23.80315
1962	14.06184
1963	16.05653
1964	19.69028
1965	28.66201
1966	28.43284
1967	29.71997
1968	23.51954
1969	25.57319
1970	25.88137
1971	26.21927
1972	23.7333
1973	25.65019
1974	20.0008
1975	11.89955
1976	9.17313
1977	10.116
1978	21.72473
1979	16.21053
1980	13.69514
1981	12.36134
1982	11.59629
1983	8.92247
1984	9.18967
1985	9.5574
1986	10.54207
1987	13.66771
1988	17.21489
1989	25.52025
1990	24.28587
1991	24.58293
1992	31.34766
1993	33.12064
1994	39.77579
1995	50.01997
1996	49.26135
1997	47.22419
1998	40.45801
1999	46.96955
2000	43.01534
2001	37.07262
2002	41.80446
2003	44.58905
2004	40.04392
2005	41.22522
2006	51.66656
2007	56.95583
2008	74.54374
2009	59.89152
2010	61.55057
2011	57.9693
2012	63.09916
2013	64.1337
2014	70.89939
2015	69.40635
2016	57.96531
2017	68.64328
2018	82.8627
2019	86.18489
2020	72.28463
2021	76.65395