Year	Percent
1995	81.36
1996	81.93
1997	80.63
1998	79.87
1999	79.79
2000	79.5
2001	79.28
2002	79.01
2003	78.44
2004	76.72
2005	76.61
2006	76.43
2007	76.42
2008	76.55
2009	76.86
2010	77.08