Year Percent 1961 -13.07176 1962 18.1518 1963 2.52536 1964 -4.99115 1965 -1.71198 1966 3.8344 1967 -3.76753 1968 1.38149 1969 6.26284 1970 -2.9921 1971 3.15457 1972 -2.49145 1973 5.29989 1974 0.39189 1975 -7.55971 1976 -7.94869 1977 -2.10018 1978 -8.02739 1979 -2.33772 1980 -0.50203 1981 -0.23102 1982 -2.89213 1983 -1.04296 1984 2.944 1985 -2.09389 1986 1.97905 1987 -0.07281 1988 -2.36105 1989 -4.27917 1990 -9.67007 1991 -11.73653 1992 -13.93017 1993 -16.78346 1994 -7.33634 1995 -2.50056 1996 -3.74182 1997 -7.89877 1998 -3.84084 1999 -6.47708 2000 -9.23976 2001 -4.76634 2002 -0.02983 2003 2.38465 2004 3.42924 2005 2.80626 2006 1.98394 2007 2.84974 2008 2.78428 2009 -0.50012 2010 3.59904 2011 3.36577 2012 3.57044 2013 4.92651 2014 5.89642 2015 3.4451 2016 -0.90338 2017 0.38121