Year Percent 1990 2.90051 1991 3.10171 1992 2.47398 1993 2.38819 1994 1.41053 1995 1.80142 1996 1.90064 1997 1.87447 1998 1.61225 1999 1.60081 2000 1.25474 2001 1.25172 2002 1.25007 2003 1.15414 2004 0.63932 2005 0.67208 2006 1.16076 2007 1.34397 2008 1.33683 2009 1.30954 2010 1.30275 2011 1.28321 2012 1.252 2013 1.22779 2014 1.58563 2015 1.58506 2016 1.55238 2017 1.56301 2018 1.54037 2019 1.52059 2020 1.62095