Year Percent 1971 11.14457 1972 3.75916 1973 5.28021 1974 4.63851 1975 0.44332 1976 5.74601 1977 9.48318 1978 6.44768 1979 4.01495 1980 7.37709 1981 -0.91378 1982 -5.34763 1983 2.26577 1984 -6.25916 1985 2.68217 1986 6.49678 1987 4.34564 1988 4.25466 1989 5.69517 1990 -12.19587 1991 0.06651 1992 -4.76852 1993 -4.85588 1994 5.35181 1995 3.171 1996 1.34801 1997 1.28773 1998 7.5659 1999 1.37788 2000 6.91102 2001 0.99946 2002 -1.42426 2003 4.14501 2004 6.78663 2005 4.78963 2006 5.85503 2007 2.74878 2008 6.59398 2009 0.87491 2010 0.69531 2011 -0.47028 2012 1.53698 2013 -1.12554 2014 5.66442 2015 0.63367 2016 7.52503