Year	Percent
1995	14.4
1996	14.51
1997	14.58
1998	15.49
1999	16.15
2000	16.42
2001	16.67
2002	17.37
2003	17.4
2004	17.75
2005	18.04
2006	17.9
2007	18.16
2008	17.91
2009	17.44
2010	17.44