Year Percent 1995 3.8846 1996 4.38898 1997 4.30221 1998 4.15041 1999 3.81738 2000 3.74531 2001 3.67764 2002 3.48902 2003 3.43116 2004 3.12833 2005 2.76905 2006 2.41168 2007 2.50795 2008 2.36846 2009 2.26545 2010 2.43113 2011 2.37327 2012 2.40829 2013 2.6215 2014 2.53523 2015 2.73409 2016 2.82425 2017 2.78703 2018 2.75622 2019 2.46894 2020 2.8115 2021 2.73078 2022 2.33835