Year % of total 1992 4.936787726988102 1993 1.997694029850746 1994 10.211898734177216 1995 8.37860534124629 1996 11.28980906921241 1997 3.325783274440518 1998 2.999033457249071 1999 3.137167300380228 2000 3.2858422939068097 2001 2.185276162790698 2002 1.9392788461538462 2003 2.492375504710633 2004 3.7447206165703273 2005 4.2702587800369685 2006 4.0744444444444445 2007 4.0766013763896245 2008 3.674065510597303 2009 2.1193443419135503 2010 2.199496161228407 2011 2.1934035383319292 2012 2.187509107468124 2013 1.7118260869565218 2014 1.7874037968188816 2015 2.0756603773584903 2016 1.8876678603401968