Year	Percent
1985	31.33
1986	39.79
1987	32.48
1988	37.8
1989	35.58
1990	44.19
1991	19.18
1992	14.24
1994	13.99
1995	9.582
1996	9.581
1998	10.95
1999	11.44
2000	12.99
2001	13.05
2002	7.159
2003	7.193
2004	7.495
2005	6.018
2006	7.183
2007	7.546
