Year	Percent
1995	22.99
1996	20.97
1997	21.63
1998	28.42
1999	29.9
2000	33.71
2001	19.63
2002	19.16
2003	16.22
2004	18.36
2005	20.57
2006	19.17
2007	21.56
2008	22.73
2009	22.05
2010	22.69