Year Percent 1971 -0.60368 1972 2.78891 1973 2.67241 1974 1.01049 1975 -3.33803 1976 -0.18118 1977 -0.28069 1978 -1.44222 1979 -3.06445 1980 -1.33076 1981 -3.94875 1982 -2.93137 1983 -2.59534 1984 -2.59835 1985 -2.02379 1986 -1.00182 1987 1.32567 1988 0.97049 1989 0.80168 1990 -0.14261 1991 -1.36613 1992 -2.87054 1993 -4.41262 1994 -0.40357 1995 0.86972 1996 3.82048 1997 9.12362 1998 3.49243 1999 3.73036 2000 1.91345 2001 1.51784 2002 2.35499 2003 7.36666 2004 3.32467 2005 3.82512 2006 1.79487 2007 -2.00718 2008 -9.87404 2009 -4.37595 2010 -5.34426 2011 -3.85185 2012 -0.03974 2013 2.39251 2014 4.29811 2015 2.40498 2016 2.85553 2017 2.29146