Year % 1995 31.66 1996 53.09 1997 56.85 1998 49.04 1999 55.13 2000 78.56 2001 48.17 2002 47.66 2003 54.08 2004 38.79 2005 46.87 2006 49 2007 42.02 2008 45.78 2009 45.78 2010 43.47 2011 47.88 2012 43.48 2013 42.81 2014 42.71 2015 40.89 2016 41.57 2017 18.81