Year Average 1990 = 100 1975-12-31 103.49 1976-12-31 105.54 1977-12-31 94.86 1978-12-31 88.17 1979-12-31 90.99 1980-12-31 93.36 1981-12-31 96.8 1982-12-31 91.37 1983-12-31 93.37 1984-12-31 94.98 1985-12-31 94.95 1986-12-31 92.3 1987-12-31 93.9 1988-12-31 96.55 1989-12-31 99.21 1990-12-31 99.22 1991-12-31 87.55 1992-12-31 77.49 1993-12-31 75.55 1994-12-31 84.42 1995-12-31 86.78 1996-12-31 84.54 1997-12-31 80.65 1998-12-31 83.06 1999-12-31 77.89 2000-12-31 78.08 2001-12-31 78.38