Year	Percent
1976	11.5
1977	11.4
1978	9.53
1981	9.51
1982	11.5
1986	11.78
1992	8.91
1993	11.54
1995	7.14
1996	7.14
1997	9.01
1998	8.55
1999	7.34
2000	5.26
2002	8.09
2003	6.62
2004	5.71
2005	6.21
2006	7.1
2007	8.28
2008	6.41