Year Percent 1985 5.9459 1986 5.03676 1987 4.66959 1988 4.48975 1989 3.96114 1990 3.82793 1991 3.60051 1992 2.68907 1993 2.41242 1994 2.24086 1995 2.26015 1996 2.62634 1997 2.96726 1998 1.86244 1999 2.27364 2000 2.92801 2001 4.00238 2002 2.73939 2003 3.99527 2004 3.83813 2005 3.05156 2006 2.69365 2008 3.49644 2009 3.98552 2012 3.73909 2013 3.51491 2014 3.61557 2015 3.76788 2016 4.0574