Year	Percent
1995	67.14
1996	60.88
1997	64.87
1998	65.19
1999	68.81
2000	72.38
2001	72.49
2002	75.17
2003	72.84
2004	69.68
2005	74.46
2006	72.84
2007	73.26
2008	71.27
2009	73.05
2010	71.74