Year Percent 1991 3.53174 1992 3.37708 1993 3.19877 1994 3.15543 1995 3.8723 1996 2.64482 1997 2.34128 1998 2.91933 1999 1.95244 2000 2.44413 2001 1.52893 2002 1.96904 2003 2.72328 2004 1.9604 2005 1.73534 2006 1.82842 2007 1.84506 2008 1.66489 2009 1.35543 2010 1.1029 2011 1.23235 2012 1.32509 2013 1.58601 2014 1.42641 2015 1.04467 2016 1.02571 2017 1.38897 2018 1.0539 2019 0.68499