Year	Percent
1991	69.76
1992	48.34
1993	46.79
1994	32.74
1995	14.08
1996	25.76
1997	21.28
1998	21.19
1999	2.823
2000	3.069
2001	18.95
2002	23.58
2003	23.73
2004	24.62
2005	17.77
2006	24.34
2007	11.45