Year	%
1985	83.95816
1986	84.17426
1987	86.67273
1988	78.20885
1989	78.87078
1990	79.88214
1991	80.99485
1992	82.10409
1993	83.20377
1994	84.35228
1995	85.42741
1996	86.49495
1997	87.51502
1998	88.5326
1999	89.55655
2000	88.26077
2001	90.69474
2002	89.03349
2003	87.62996
2004	87.94861
2005	88.66733
2006	89.49697
2007	89.45987
2008	89.78716
2009	90.29645
2010	90.37052
2011	90.69518
2012	90.15394
2013	90.36482
2014	89.3424
2015	90.53455
2016	89.67192
2017	91.34762