Year	Percent
1980	96.45532
1981	96.06848
1983	94.83968
1984	91.38862
1985	92.26921
1986	95.00643
1992	104.32438
1994	102.56624
1995	100.71063
1996	100.29558
1997	103.32162
1998	100.67829
1999	99.36984
2000	95.99784
2001	95.25782
2002	99.64511
2004	108.74463
2006	111.50507
2008	106.28892
2009	105.26316
2011	104.03355
2012	103.21157
2013	102.83697
2015	106.06348