Year Percent 1990 10.5 1991 10.9 1992 11.3 1993 11.7 1994 12.1 1995 12.5 1996 12.5 1997 12.5 1998 12.5 1999 12.5 2000 8.1 2004 8.37 2006 17.36 2008 17.04