Year Percent 1990 1.97892 1991 1.90166 1992 1.83559 1993 1.76373 1994 1.69709 1995 2.12148 1996 2.06942 1997 3.28191 1998 3.16382 1999 3.4845 2000 3.41899 2001 3.33706 2002 3.39784 2003 3.23043 2004 3.26248 2005 3.21701 2006 3.3143 2007 3.26028 2008 3.21068 2009 3.16722 2010 2.92831 2011 2.86596 2012 2.80861 2013 2.68957 2014 2.81222 2015 2.70884 2016 2.66143 2017 2.62696 2018 2.5938 2019 2.5572 2020 2.74924