Year Percent 1991 7.607 1992 7.777 1993 7.381 1994 7.277 1995 7.178 1996 7.047 1997 6.369 1998 5.949 1999 6.984 2000 8.062 2001 7.45 2002 6.525 2003 7.03 2004 7.541 2005 6.482 2006 6.262 2007 5.393 2008 4.743 2009 4.849 2010 4.559 2011 4.422 2012 4.23 2013 3.938 2014 4.251 2015 4.177 2016 4.682 2017 4.658 2018 4.659 2019 4.66 2020 4.66 2021 4.661 2022 4.661