Year	Percent
1995	82.42
1996	70.22
1997	80.9
1998	79.58
1999	79.07
2000	78.76
2001	78.73
2002	72.67
2003	79.29
2004	79.17
2005	79.22
2006	79.38
2007	73.44
2008	79.55
2009	81.14
2010	81.38
2011	81.4