Year	Percent
1995	38.52
1996	41
1997	38.56
1998	42.51
1999	43.38
2000	45.22
2001	45.45
2002	46.64
2003	47.26
2004	49.32
2005	52.64
2006	62.02
2007	59.08
2008	59.41
2009	60.28
2010	61.7