Year	Percent
1995	57.62
1996	49.71
1997	51.77
1998	51.37
1999	48.48
2000	44.28
2001	41.14
2002	39.55
2003	37.89
2004	40.83
2005	40.89
2006	46.16
2007	49.15
2008	48.4
2009	53.04
2010	56.19