Year	Percent
1995	28.88
1996	24.68
1997	17.68
1998	22.96
1999	23.49
2000	24.51
2001	28.45
2002	29.51
2003	26.16
2004	25.26
2005	27.06
2006	29.77
2007	30.85
2008	34.92
2009	35.98
2010	22.31