Year Percent 1961 2.15005 1962 1.35317 1963 3.60871 1964 0.18055 1965 2.02734 1966 1.30107 1967 2.24708 1968 1.93203 1969 1.67636 1970 0.81686 1971 2.43516 1972 2.45971 1973 5.84868 1974 0.65931 1975 2.63734 1976 5.81858 1977 2.7252 1978 2.32179 1979 2.78135 1980 2.30267 1981 0.62383 1982 0.81943 1983 -0.87056 1984 -9.81077 1985 -9.78021 1986 0.67324 1987 1.56478 1988 3.9735 1989 3.48535 1990 0.44974 1991 -3.02223 1992 -2.07854 1993 -0.29642 1994 1.96139 1995 2.28118 1996 3.46011 1997 2.85511 1998 -2.74496 1999 0.86444 2000 2.19458 2001 0.73221 2002 1.49692 2003 2.84662 2004 4.62293 2005 2.83968 2006 3.40299 2007 4.84468 2008 2.47903 2009 -0.46289 2010 5.90312 2011 1.97196 2012 4.93411 2013 5.30893 2014 4.42621 2015 4.38341 2016 5.21666 2017 5.05975