Year Percent 1990 3.28537 1991 2.72229 1992 2.5183 1993 1.34594 1994 2.09755 1995 3.61369 1996 3.7129 1997 3.72001 1998 3.78487 1999 3.26053 2000 3.28984 2001 3.19043 2002 3.01717 2003 2.55794 2004 2.53445 2005 2.58921 2006 2.22577 2007 2.18486 2008 2.15113 2009 1.91544 2010 1.91779 2011 1.42319 2012 1.41816 2013 1.40642 2014 1.40863 2015 1.41894 2016 0.95851 2017 0.92145 2018 1.10681 2019 1.09084 2020 1.1172