Year	Percent
1995	16.89
1996	18.06
1997	18.08
1998	23.01
1999	27.49
2000	29.97
2001	30.48
2002	30.86
2003	32.83
2004	33.24
2005	31.32
2006	29.97
2007	29.74
2008	29.02
2009	30.09
2010	31.4