Year	Percent
1972	39.40046
1973	39.30082
1974	23.80104
1975	27.81329
1976	35.70155
1977	38.19935
1978	46.2
1979	59.59138
1980	49.35176
1981	74.04667
1982	66.256
1983	60.29238
1984	53.0566
1985	46.12696
1986	42.04167
1987	109.975
1988	86.27345
1989	96.16538
1990	117.86745
1991	94.70361
1992	123.32077
1993	103.37391
1994	81.88093
1995	104.14368
1996	92.4
1997	91.36
1998	80.14
1999	93.86916
2000	93.20741
2001	97.78828
2002	110.01371
2003	93.04521
2004	91.00839
2005	111.29424
2006	90.87844
2007	88.92044
2008	89.21445
2009	87.57301
2010	79.89484
2011	85.79382
2012	92.8351
2013	92.77594
2014	94.94168
2015	103.44537
2016	95.6093
2017	95.41425