Year Percent 1961 5.06445 1962 3.10996 1963 -0.26412 1964 4.42103 1965 2.75243 1966 0.18838 1967 23.62919 1968 5.75073 1969 5.30196 1970 7.884 1971 3.44012 1972 7.97638 1973 6.52953 1974 10.65609 1975 5.99007 1976 19.67444 1977 5.88477 1978 3.40981 1979 12.85277 1980 14.24589 1981 8.80019 1982 12.48195 1983 12.76307 1984 13.55219 1985 11.18713 1986 0.17924 1987 -2.39231 1988 0.8139 1989 -1.81908 1990 1.6431 1991 3.56871 1992 -1.27767 1993 39.80023 1994 9.61874 1995 4.99279 1996 1.07276 1997 5.5889 1998 4.30829 1999 -1.11977 2000 5.21482 2001 1.46067 2002 1.84166 2003 0.19581 2004 1.98601 2005 0.74897 2006 3.35866 2007 0.95776 2008 6.61278 2009 1.64518 2010 1.90983 2011 2.67023 2012 2.6709 2013 2.04115 2014 2.09607 2015 0.17915 2016 0.03055 2017 2.76021