Year	%
1985	77.77073
1986	77.88537
1987	78.4576
1988	77.30675
1989	78.01279
1990	79.81551
1991	81.088
1992	82.76177
1993	82.59613
1994	83.9193
1995	86.17113
1996	86.76505
1997	86.75155
1998	86.88137
1999	87.53948
2000	87.86488
2001	89.15952
2002	89.38276
2003	89.53735
2004	89.58607
2005	90.42706
2006	91.35401
2007	91.53891
2008	91.49653
2009	91.43735
2010	91.44477
2011	91.68801
2012	90.6942
2013	90.50994
2014	90.66304
2015	91.1741
2016	90.86857
2017	91.3076