Year	US Dollars
1960	1.35119
1961	3.481
1962	6.03822
1963	11.79253
1964	5.71269
1965	9.26112
1966	7.60991
1967	6.2045
1968	11.69987
1969	7.14444
1970	2.47763
1971	6.48519
1972	8.70569
1973	11.15175
1974	17.12881
1975	13.11777
1976	17.1706
1977	32.59532
1978	50.78948
1979	49.3559
1980	73.25497
1981	90.7052
1982	60.01781
1983	50.75651
1984	62.74264
1985	56.12425
1986	114.06331
1987	111.79612
1988	86.61199
1989	98.68645
1990	93.46387
1991	91.86589
1992	96.56195
1993	72.66913
1994	57.12831
1995	36.57354
1996	28.19236
1997	29.53678
1998	29.08887
1999	24.59722
2000	34.53124
2001	35.64165
2002	42.35253
2003	40.40844
2004	38.0468
2005	36.5943
2006	43.94335
2007	55.07447
2008	51.97902
2009	66.64647
2010	62.51048
2011	67.91572
2012	67.43282
2013	52.85032
2014	45.83788
2015	50.56959
2016	39.69867
2017	119.47427
2018	95.76198
2019	75.67113
2020	116.82618
2021	92.79841