Year	Percent
1995	16.04
1996	16.06
1997	17.03
1998	18.44
1999	18.34
2000	18.25
2001	17.94
2002	16.49
2003	17.11
2004	18.08
2005	17.65
2006	19.41
2007	19.84
2008	23.61
2009	21.22
2010	19.87