Year Percent 1960-01-01 17.855000000000000 1961-01-01 17.449100000000000 1962-01-01 17.295900000000000 1963-01-01 17.713700000000000 1964-01-01 18.123800000000000 1965-01-01 19.491800000000000 1966-01-01 23.488000000000003 1967-01-01 28.068400000000000 1968-01-01 29.681400000000000 1969-01-01 30.797100000000000 1970-01-01 31.940000000000000 1971-01-01 32.653100000000000 1972-01-01 34.907200000000000 1973-01-01 36.521000000000000 1974-01-01 37.450100000000000 1975-01-01 39.493400000000000 1976-01-01 40.733800000000000 1977-01-01 44.234100000000000 1978-01-01 48.080200000000000 1979-01-01 50.966600000000000 1980-01-01 52.956200000000000 1981-01-01 59.950200000000000 1982-01-01 68.341000000000010 1983-01-01 63.321800000000000 1984-01-01 60.514600000000000 1985-01-01 60.966900000000000 1986-01-01 62.076200000000000 1987-01-01 61.534600000000000 1988-01-01 62.917700000000000 1989-01-01 66.518100000000000 1990-01-01 70.783999999999990 1991-01-01 75.210800000000000 1992-01-01 75.312200000000000 1993-01-01 74.951600000000000 1994-01-01 72.807300000000000 1995-01-01 73.212400000000000 1996-01-01 75.443700000000000 1997-01-01 78.563200000000000 1998-01-01 79.876400000000000 1999-01-01 76.431300000000000 2000-01-01 72.555500000000000 2001-01-01 97.408800000000000 2002-01-01 118.420000000000000 2003-01-01 113.742000000000000 2004-01-01 111.634000000000000 2005-01-01 115.893999999999990 2006-01-01 125.850000000000000 2007-01-01 126.601000000000000 2008-01-01 122.694000000000000