Year Percent 1991 2.99572 1992 2.8956 1993 2.63171 1994 2.88841 1995 2.6784 1996 2.74539 1997 2.65649 1998 2.2378 1999 2.39299 2000 1.90791 2001 1.3796 2002 1.78979 2003 1.7211 2004 2.2188 2005 2.03894 2006 1.95431 2007 1.85603 2008 1.55279 2009 1.48706 2010 1.35199 2011 1.3005 2012 1.172 2013 1.3598 2014 1.2182 2015 1.1765 2016 1.25129 2017 1.1636 2018 0.9943 2019 0.91948