Year Percent 1990 5.69521 1991 4.75126 1992 5.30739 1993 4.93433 1994 4.73136 1995 6.38305 1996 6.28205 1997 6.19134 1998 6.08196 1999 5.95967 2000 5.8636 2001 5.73837 2002 5.39344 2003 5.24122 2004 4.94597 2005 4.85395 2006 4.75364 2007 4.55108 2008 4.35488 2009 4.16776 2010 3.69585 2011 3.09617 2012 2.64207 2013 2.34636 2014 2.19625 2015 2.07975 2016 1.95574 2017 1.88947 2018 1.86964 2019 1.925 2020 2.13257