Year % of total 1992 25.15923766816143 1993 14.061771286513364 1994 10.712978927203064 1995 4.976002444987775 1996 37.880801886792455 1997 47.29898550724638 1998 60.84721442885771 1999 56.140796460176986 2000 44.511383647798745 2001 47.60849431818181 2002 54.13780405405405 2003 54.30873417721519 2004 46.027922848664694 2005 44.02129716981132 2006 44.62817021276596 2007 44.81165186500888 2008 45.61020661157025 2009 49.98081850533808 2010 51.972142857142856 2011 41.56308282208589 2012 37.843031988873435 2013 33.91039540816326 2014 33.46624557260921 2015 34.99593478260869 2016 40.242