Year Percent 1960-01-01 16.994700000000000 1961-01-01 17.447100000000000 1962-01-01 18.320200000000000 1963-01-01 18.749100000000000 1964-01-01 18.731200000000000 1965-01-01 19.182700000000000 1966-01-01 20.216700000000000 1967-01-01 21.392100000000000 1968-01-01 22.736200000000000 1969-01-01 26.442400000000000 1970-01-01 29.021300000000000 1971-01-01 29.922200000000000 1972-01-01 31.147700000000000 1973-01-01 32.059600000000000 1974-01-01 31.128600000000000 1975-01-01 31.580900000000000 1976-01-01 32.013100000000000 1977-01-01 32.975500000000000 1978-01-01 32.926000000000000 1979-01-01 33.086999999999996 1980-01-01 32.251300000000000 1981-01-01 32.443500000000000 1982-01-01 32.650999999999996 1983-01-01 33.698800000000000 1984-01-01 33.589600000000000 1985-01-01 33.598300000000000 1986-01-01 34.737100000000000 1987-01-01 37.238300000000000 1988-01-01 37.423600000000000 1989-01-01 37.689100000000000 1990-01-01 38.453300000000000 1991-01-01 38.749400000000000 1992-01-01 52.537100000000000 1993-01-01 68.930500000000000 1994-01-01 69.780100000000000 1995-01-01 69.950500000000000 1996-01-01 73.601600000000000 1997-01-01 76.054300000000000 1998-01-01 76.054300000000000 1999-01-01 76.054300000000000 2000-01-01 82.739600000000000 2001-01-01 80.270000000000000 2002-01-01 80.462300000000000 2003-01-01 83.896200000000000 2004-01-01 86.932700000000000 2005-01-01 90.909800000000000 2006-01-01 92.049800000000000 2007-01-01 90.635100000000000 2008-01-01 92.368600000000000 2009-01-01 95.082800000000000 2010-01-01 95.416000000000000 2011-01-01 96.298700000000000 2012-01-01 98.122900000000000 2013-01-01 101.216000000000010 2014-01-01 104.546000000000000 2015-01-01 108.402999999999990 2016-01-01 110.648000000000000