Year	Percent
1995	61.48
1996	59
1997	61.44
1998	57.49
1999	56.62
2000	54.78
2001	54.55
2002	53.36
2003	52.74
2004	50.68
2005	47.36
2006	37.98
2007	40.92
2008	40.59
2009	39.72
2010	38.3