Year	%
1984	90.57631
1985	90.5641
1986	89.81506
1987	89.91783
1988	88.81727
1989	89.31814
1990	89.69103
1991	90.52738
1992	91.86048
1993	92.7813
1994	92.64753
1995	93.13022
1996	94.88035
1997	95.28747
1998	96.08363
1999	96.60882
2000	96.86632
2001	95.65609
2002	95.81996
2003	97.43229
2004	98.30159
2005	99.27757
2006	99.30865
2007	99.22493
2008	99.06604
2009	99.11702
2010	99.23653
2011	99.35197
2012	97.22839
2013	98.43894
2014	98.70004
2015	99.56542
2016	99.5262
2017	99.65062