Year Percent 1971 -0.48808 1972 -0.28146 1973 -0.18725 1974 -0.18003 1975 -0.28761 1976 2.59572 1977 2.55549 1978 2.56799 1979 2.76205 1980 3.0617 1981 3.38393 1982 -2.67015 1983 -0.40049 1984 3.33594 1985 6.05467 1986 2.99114 1987 8.13854 1988 4.53215 1989 3.34433 1990 1.04349 1991 0.53862 1992 2.24193 1993 2.86052 1994 5.2965 1995 4.26852 1996 5.22621 1997 5.49744 1998 6.03935 1999 8.77369 2000 1.84334 2001 -1.86813 2002 -2.00383 2003 -2.8033 2004 2.22013 2005 4.05808 2006 7.89271 2007 2.66193 2008 1.17082 2009 -1.77929