Year	Percent
1995	73.88
1996	71.44
1997	70.79
1998	65.09
1999	61.86
2000	59.88
2001	58.66
2002	58.95
2003	58.81
2004	59.58
2005	61.98
2006	63.23
2007	64.18
2008	64.31
2009	63.35
2010	62.08