Year	Percent
1974	12.44371
1975	13.70639
1977	15.21499
1978	13.53485
1979	14.93358
1980	14.94413
1981	25.07096
1982	23.82218
1983	19.49132
1984	29.81413
1985	30.40965
1986	35.57473
1987	39.96429
1988	45.88205
1990	58.78109
1994	73.51559
1998	102.32678
2000	106.80934
2001	99.61625
2002	100.44757
2003	102.8169
2004	99.11604
2005	87.62553
2006	99.95092
2007	93.5745
2008	99.13116
2009	91.66244
2010	92.88159
2011	89.88589
2012	89.33193
2013	84.19007
2014	85.30408
2015	89.43016
2016	84.77515