Year Percent 1995 16.0144 2000 12.3711 2001 13.7756 2002 17.0134 2003 18.2287 2004 20.0312 2005 22.2124 2006 20.5166 2007 19.0628 2008 24.161 2009 26.3839 2010 26.7553 2011 28.374 2012 32.9043 2013 35.0365 2014 38.4426 2015 39.0601 2016 44.75 2017 47.3925