Year Percent 1971 2.24668 1972 3.27656 1973 5.71074 1974 3.80606 1975 -3.62495 1976 0.03974 1977 -4.23498 1978 0.28593 1979 2.59282 1980 1.15739 1981 4.25278 1982 -0.06764 1983 2.09473 1984 3.89027 1985 0.98878 1986 2.73111 1987 -5.13228 1988 1.72443 1989 0.0445 1990 -0.2753 1991 -6.29434 1992 0.21704 1993 5.32501 1994 3.82707 1995 3.05698 1996 1.73502 1997 1.66539 1998 0.17334 1999 4.64241 2000 1.69019 2001 3.18778 2002 3.25127 2003 2.49733 2004 1.74617 2005 2.15923 2006 1.33015 2007 2.79744 2008 -2.37758 2009 0.90226 2010 -0.15405 2011 1.91574 2012 1.93903 2013 1.23716 2014 1.99286 2015 2.48 2016 1.32186 2017 0.86445