Year	Percent
1995	16.4
1996	16.59
1997	16.82
1998	16.8
1999	16.83
2000	17.1
2001	17.77
2002	18.21
2003	18.83
2004	19.2
2005	19.13
2006	19.75
2007	19.66
2008	19.41
2009	19.64
2010	22.35