Year	Percent
1995	80.11619
1996	78.92183
1997	80.91709
1998	81.31988
1999	82.12871
2000	83.38649
2001	85.07238
2002	85.1031
2003	81.33021
2004	84.61164
2005	82.24461
2006	81.87185
2007	80.03099
2008	82.58046
2009	78.31869
2010	84.72326
2011	82.57461
2012	81.86313
2013	80.90888
2014	77.8371
2015	76.00916
2016	77.09996
2017	79.57338