Year Percent 1966 -6.93365 1967 2.12408 1968 10.81745 1969 10.70936 1970 21.6422 1971 -0.13407 1972 -1.13291 1973 -13.27248 1974 10.55033 1975 5.29382 1976 1.15485 1977 0.4013 1978 8.60219 1979 -14.22383 1980 -1.50232 1981 -8.69506 1982 0.25641 1983 -3.97713 1984 -0.18028 1985 2.60554 1986 -2.8246 1987 3.62552 1988 32.00917 1989 8.83983 1990 1.17457 1991 2.2303 1992 -1.96059 1993 -2.02955 1994 -0.10936 1995 3.57106 1996 -1.45576 1997 0.05531 1998 -5.02094 1999 -0.99761 2000 0.17714