Year	Percent
1995	60.15
1996	59.9
1997	58.19
1998	55.08
1999	53.25
2000	52.39
2001	52.5
2002	52.91
2003	53.33
2004	52.82
2005	55.73
2006	52.79
2007	55.04
2008	54.77
2009	53.17
2010	54.4