Year % 1990 25.08 1992 25.32 1995 28.68 1998 30.13 2000 41.38 2002 44.04 2003 38.16 2004 37.85 2005 26.63 2006 32.23 2008 26.74 2009 25.05 2010 17.86 2011 22.34 2012 22.14 2013 12.27 2015 11.86 2016 19.53