Year Years 1980 -1.128 1981 -0.4851 1982 -0.2919 1983 -0.1111 1984 0.1395 1985 1.408 1986 2.208 1987 1.862 1988 3.071 1989 3.923 1990 3.912 1991 3.102 1992 2.977 1993 2.949 1994 2.99 1995 1.993 1996 2.109 1997 2.824 1998 0.8453 1999 -0.09922 2000 -0.4049 2001 -0.3985 2002 0.5498 2003 0.6408