Year Percent 1983 12.02 1984 11 1986 6.7 1988 4.39 1989 3.53 1990 4.23 1991 3.94 1992 3.27 1993 3.3 1994 4.59 1995 3.49 1996 5.29 1997 5.18 1998 5.48 1999 8.87 2000 8.23 2001 8.44 2002 8.14 2003 7.75 2004 8.33 2005 7.53 2006 7.36 2007 6.64 2008 7.27 2009 9.36 2010 7.39 2011 6.21 2012 5.71 2013 5.31 2014 5.75 2015 5.94 2016 6.29 2017 6.57 2018 6.89 2019 7.04 2020 10.83