Year Percent 1991 1.21812 1992 2.81598 1993 -1.12983 1994 1.81577 1995 1.33817 1996 0.88934 1997 1.89951 1998 2.94965 1999 0.89787 2000 3.23178 2001 0.8944 2002 1.02885 2003 0.8533 2004 1.09001 2005 2.68885 2006 0.35423 2007 0.53034 2008 0.84369 2009 1.06991 2010 4.81959 2011 -15.03783 2012 -0.31078 2013 2.0924 2014 -2.73653 2015 -38.71102 2016 -35.92985