Year	Percent
1995	52.99
1996	52.82
1997	46.05
1998	45.18
1999	45.11
2000	43.85
2001	43.62
2002	36.48
2003	36.21
2004	35.09
2005	35.61
2006	27.3
2007	23.67
2008	23.85
2009	25.41
2010	24.96