Year % 1990 17.43 1992 17.27 1995 18.72 1998 18.54 2000 22.55 2002 28.54 2003 19.87 2004 18.47 2005 12.19 2006 13.92 2008 11.97 2009 16.23 2010 8.9 2011 14.43 2012 11.6 2013 6.11 2015 5.98 2016 9.07