Year Percent 1961 9.16119 1962 7.89866 1963 7.37559 1964 10.51914 1965 4.68856 1966 9.63296 1967 10.051 1968 12.50717 1969 10.17649 1970 -0.72959 1971 3.35976 1972 6.9055 1973 7.14198 1974 -3.09292 1975 1.45412 1976 3.2088 1977 3.38919 1978 4.32365 1979 4.59917 1980 2.01465 1981 3.44226 1982 2.61382 1983 2.81992 1984 3.84112 1985 4.59198 1986 2.69887 1987 4.21684 1988 6.3304 1989 4.42963 1990 4.53525 1991 3.09703 1992 0.59804 1993 -0.76316 1994 0.64958 1995 2.35063 1996 2.83929 1997 0.8355 1998 -1.39671 1999 -0.43391 2000 2.60785 2001 0.1647 2002 -0.11454 2003 1.3112 2004 2.17029 2005 1.65312 2006 1.35575 2007 1.53744 2008 -1.14142 2009 -5.40459 2010 4.17303 2011 0.06976 2012 1.65732 2013 2.14753 2014 0.508 2015 1.46144 2016 1.05463 2017 1.88002