Year	Percent
1995	30.36
1996	30.79
1997	29.91
1998	31.18
1999	30.76
2000	32.46
2001	33.01
2002	33.44
2003	33.07
2004	32.79
2005	30.96
2006	30.02
2007	29.3
2008	28.78
2009	29.91
2010	26.68