Year Percent 1991 8.315 1992 7.853 1993 7.282 1994 7.527 1995 7.684 1996 8.557 1997 8.41 1998 8.321 1999 7.926 2000 8.525 2001 8.426 2002 8.431 2003 8.525 2004 8.592 2005 8.747 2006 9.73 2007 9.817 2008 9.428 2009 9.323 2010 8.959 2011 9.02 2012 8.737 2013 8.503 2014 8.309 2015 7.888 2016 7.491 2017 7.498 2018 7.432 2019 7.353 2020 7.282 2021 7.202 2022 7.139