Year Percent 1974 1.121 1975 2.622 1988 3.612 1989 6.248 1990 10.09 1991 3.407 1992 0.7526 1993 0.9363 1994 2.132 1995 5.193 1996 6.814 1997 2.852 1998 3.976 1999 12.29 2000 9.188 2001 8.113 2002 6.165 2003 6.606 2004 9.777 2005 8.101 2006 7.981 2007 5.446