Year	Percent
1995	60.47
1996	59.02
1997	56.95
1998	57.07
1999	55.8
2000	52.43
2001	55.83
2002	59.99
2003	59.77
2004	60.19
2005	60.77
2006	64.62
2007	65.23
2008	67.62
2009	64.88
2010	64.66