Year % of total 1992 10.975276695245517 1993 10.384424778761062 1994 10.588765613519472 1995 11.809412577747063 1996 10.912262916939175 1997 11.56282263191354 1998 12.112929032258064 1999 13.108725687458081 2000 13.01356258596974 2001 12.660448634590377 2002 12.097319587628865 2003 13.459935149156937 2004 13.094761298535964 2005 13.35128688010044 2006 12.635524218271 2007 12.84574846625767 2008 11.576670500287522 2009 12.254816484224081 2010 12.50166350411132 2011 10.74689764780674 2012 10.732682926829268 2013 10.850301369863013 2014 10.886841305998482 2015 11.555087319665908 2016 11.582770997846376