Year Percent 1990 0.06593 1991 0.12694 1992 0.66642 1993 0.68922 1994 0.45785 1995 -1.42297 1996 -0.09923 1997 -0.27991 1998 -0.37926 1999 -0.36198 2000 -0.31952 2001 -0.17195 2002 -0.09215 2003 -0.21274 2004 -0.23333 2005 -0.30043 2006 -0.3932 2007 -0.40546 2008 -0.42571 2009 -0.40099 2010 -0.40201 2011 -0.78947 2012 -0.4853 2013 -0.48659 2014 -0.46949 2015 -0.49477 2016 -0.52369 2017 -0.51211