Year	Percent
1995	26.67
1996	26.06
1997	25.18
1998	18.66
1999	25.13
2000	26.57
2001	21.88
2002	22.02
2003	22.31
2004	21.8
2005	22.06
2006	21.68
2007	22.57
2008	22.51
2009	22.36
2010	22.35