Year	%
1984	86.9234
1985	90.18858
1986	89.7167
1987	89.71563
1988	89.23614
1989	88.57652
1990	84.29588
1991	84.05804
1992	83.65079
1993	84.26286
1994	85.09685
1995	85.95135
1996	85.8917
1997	86.49668
1998	87.08132
1999	87.18327
2000	89.10712
2001	86.2868
2002	88.92492
2003	89.58487
2004	90.45716
2005	91.08186
2007	94.25279
2008	92.45158
2009	93.81522
2010	92.45956
2011	91.39073
2012	89.45412
2013	90.7315
2014	88.15399
2015	89.06486
2016	90.27354
2017	92.27973