Year	Percent
1995	52.07
1996	54.6
1997	57.34
1998	58.21
1999	67.94
2000	71.65
2001	72.14
2002	71.91
2003	71.98
2004	71.66
2005	72.76
2006	73.3
2007	70.76
2008	64.6
2009	62.39
2010	62.86