Year	Percent
1992	44.1
1993	44.1
1994	44.1
1995	44.1
1996	43.1
1997	43.4
1998	43.4
2001	43.7
2002	43.9
2003	43.9
2006	38.04
2007	37.72
2008	37.65
2009	37.97