Year	Percent
1960	109.42642
1961	103.98432
1962	103.0838
1963	84.89014
1964	80.45643
1965	78.88323
1966	75.09022
1967	72.2082
1968	75.2815
1969	77.19693
1970	79.89631
1971	72.82851
1972	66.08413
1973	71.76657
1974	87.93076
1975	79.67479
1976	82.52286
1977	80.83574
1978	81.38503
1979	89.22138
1980	97.10049
1981	93.36698
1982	91.12682
1983	90.05236
1984	90.32361
1985	88.91941
1986	88.61146
1987	95.2094
1988	106.77344
1989	122.39576
1990	133.35854
1991	144.47085
1992	136.26986
1993	138.69761
1994	159.03225
1995	170.9093
1996	155.4162
1997	157.7616
1998	182.38617
1999	188.78457
2000	192.12337
2001	174.46014
2002	172.46918
2003	170.60002
2004	185.8072
2005	178.31995
2006	178.98358
2007	166.43741
2008	154.13421
2009	138.93221
2010	142.43548
2011	139.47189
2012	134.81937
2013	134.32058
2014	130.97536
2015	126.56074
2016	120.75751
2017	131.31575