Year Percent 1960-01-01 55.86820000000000 1961-01-01 54.53090000000000 1962-01-01 55.60390000000000 1963-01-01 57.04990000000000 1964-01-01 57.31840000000000 1965-01-01 61.49570000000000 1966-01-01 68.06380000000000 1967-01-01 71.75480000000000 1968-01-01 72.27070000000000 1969-01-01 74.10770000000000 1970-01-01 75.01260000000000 1971-01-01 76.41100000000000 1972-01-01 81.41030000000000 1973-01-01 84.50340000000000 1974-01-01 85.96620000000000 1975-01-01 87.11450000000000 1976-01-01 87.94480000000000 1977-01-01 89.90380000000000 1978-01-01 93.35670000000000 1979-01-01 95.94990000000000 1980-01-01 97.34260000000000 1981-01-01 102.59600000000000 1982-01-01 104.87700000000001 1983-01-01 102.42700000000000 1984-01-01 102.33100000000000 1985-01-01 104.10400000000000 1986-01-01 103.53600000000000 1987-01-01 102.91300000000000 1988-01-01 103.96400000000000 1989-01-01 103.74900000000000 1990-01-01 103.46300000000000 1991-01-01 103.40700000000001 1992-01-01 102.35000000000000 1993-01-01 101.94700000000000 1994-01-01 102.63900000000000 1995-01-01 102.30600000000000 1996-01-01 104.63900000000000 1997-01-01 110.04700000000001 1998-01-01 112.24100000000000 1999-01-01 111.36200000000001 2000-01-01 109.66600000000000 2001-01-01 89.56700000000001 2002-01-01 80.61920000000000 2003-01-01 80.30810000000000 2004-01-01 81.68820000000000 2005-01-01 83.69770000000000 2006-01-01 85.83100000000000 2007-01-01 98.32390000000000 2008-01-01 108.82300000000000