Year	Percent
1995	50.01
1996	48.25
1997	46.48
1998	46.3
1999	43.32
2000	40.5
2001	43.85
2002	46.78
2003	46.88
2004	46.91
2005	49.17
2006	52.26
2007	54.35
2008	56.41
2009	54.21
2010	54.03