Year Average 1990 = 100 1975-12-31 61.63 1976-12-31 66.12 1977-12-31 71.64 1978-12-31 75.52 1979-12-31 78.77 1980-12-31 79.17 1981-12-31 76.11 1982-12-31 80.6 1983-12-31 84.59 1984-12-31 84.24 1985-12-31 84.68 1986-12-31 91.98 1987-12-31 97.26 1988-12-31 96.62 1989-12-31 95.88 1990-12-31 100 1991-12-31 99.15 1992-12-31 102.13 1993-12-31 106.11 1994-12-31 106.4 1995-12-31 111.88 1996-12-31 108.9 1997-12-31 103.89 1998-12-31 104.16 1999-12-31 102.06 2000-12-31 97.87 2001-12-31 98.53