Year	Percent
1995	17.48
1996	17.58
1997	17.72
1998	17.92
1999	16.05
2000	16.14
2001	15.82
2002	15.51
2003	15.45
2004	15.73
2005	15.52
2006	15.36
2007	15.27
2008	15.05
2009	14.96
2010	14.89