Year	Percent
1985	8.25811
1986	8.01995
1987	7.94905
1988	7.28055
1989	7.09474
1990	7.23622
1991	7.93273
1992	8.89979
1993	9.51635
1994	10.04547
1995	9.72233
1996	12.29385
1997	12.62035
1998	13.54653
1999	12.03979
2000	12.3308
2001	11.78255
2002	13.18411
2003	12.973
2004	15.01635
2005	16.21516
2006	16.81617
2007	16.96487