Year % 1993 14.89 1994 19 1995 11.35 1996 25.64 1997 15.75 1998 16.57 1999 14.47 2000 11.46 2001 9.76 2002 12.82 2003 10.98 2004 9.12 2005 10.99 2006 10.37 2007 10.53 2008 33.57 2009 9.12 2010 10.45 2011 9.57 2012 9.76 2013 10.33 2014 9.52 2015 10.48 2016 9.51 2017 10.5