Year	Percent
1995	50.54
1996	48.99
1997	48.51
1998	54.15
1999	52.51
2000	51.35
2001	45.06
2002	37.24
2003	35.73
2004	30.69
2005	30.44
2006	30.07
2007	29.76
2008	31.91
2009	36.12
2010	36.3