Year	Percent
1995	27.11
1996	26.61
1997	28.04
1998	34.62
1999	28.87
2000	29.97
2001	28.1
2002	25.44
2003	26.43
2004	28.11
2005	26.12
2006	25.59
2007	24.23
2008	22.42
2009	22.3
2010	22.06