Year Percent 1991 2.204 1992 2.487 1993 1.788 1994 1.631 1995 1.633 1996 1.59 1997 1.556 1998 1.512 1999 1.453 2000 1.122 2001 0.946 2002 1.092 2003 1.058 2004 1.571 2005 1.48 2006 1.277 2007 1.305 2008 1.031 2009 0.987 2010 0.89 2011 0.886 2012 0.694 2013 0.841 2014 0.838 2015 0.729 2016 0.754 2017 0.768 2018 0.753 2019 0.735 2020 0.718 2021 0.7 2022 0.682