Year Percent 1991 0.10528 1992 -0.54306 1993 0.45221 1994 0 1995 0 1996 -0.14176 1997 0 1998 0 1999 -0.28787 2000 0.28064 2001 0.02944 2002 0.01908 2003 0 2004 0.02136 2005 0 2006 0 2007 0 2008 0 2009 0 2010 0 2011 0 2012 0 2013 0 2014 0 2015 0 2016 0.742