Year	Percent
1995	34.93
1996	32.73
1997	30.54
1998	30.36
1999	22.34
2000	18.92
2001	18.49
2002	18.91
2003	18.4
2004	18.17
2005	16.47
2006	15.4
2007	16.83
2008	18.81
2009	19.66
2010	18.63