Year	Percent
1995	23.5
1996	23.84
1997	24.57
1998	23.89
1999	23.72
2000	23.17
2001	24.69
2002	25.37
2003	25.89
2004	27.89
2005	29.73
2006	31.01
2007	32.73
2008	33.12
2009	32.59
2010	31.9