Year Percent 1962-01-01 241.070000000000000 1963-01-01 238.944000000000020 1964-01-01 239.921000000000000 1965-01-01 225.247000000000000 1966-01-01 203.930999999999980 1967-01-01 196.639000000000000 1968-01-01 189.629000000000020 1969-01-01 175.422000000000000 1970-01-01 169.182000000000020 1971-01-01 171.680000000000000 1972-01-01 164.145000000000000 1973-01-01 153.793000000000000 1974-01-01 146.802000000000020 1975-01-01 145.897000000000020 1976-01-01 135.676000000000020 1977-01-01 125.603000000000000 1978-01-01 120.415000000000000 1979-01-01 126.113999999999990 1980-01-01 146.671000000000000 1981-01-01 145.797000000000000 1982-01-01 142.398000000000000 1983-01-01 167.367000000000020 1984-01-01 184.805999999999980 1985-01-01 185.139000000000000 1986-01-01 176.562000000000000 1987-01-01 168.263000000000000 1988-01-01 156.864000000000000 1989-01-01 129.868000000000000 1990-01-01 130.332000000000000 1991-01-01 132.827000000000000 1992-01-01 113.943000000000000 1993-01-01 100.290000000000000 1994-01-01 89.115900000000000 1995-01-01 82.266700000000000 1996-01-01 76.925800000000000 1997-01-01 69.267500000000000 1998-01-01 66.999200000000000 1999-01-01 63.221900000000000 2000-01-01 61.570900000000000 2001-01-01 58.266999999999996 2002-01-01 51.814600000000000 2003-01-01 52.396400000000000 2004-01-01 56.929300000000000 2005-01-01 63.760400000000000 2006-01-01 66.730600000000000 2007-01-01 63.041600000000000 2008-01-01 66.025300000000000 2009-01-01 68.280200000000000 2010-01-01 67.673600000000000 2011-01-01 65.621300000000000 2012-01-01 62.637000000000000 2013-01-01 66.412400000000000 2014-01-01 72.916500000000000 2015-01-01 75.329300000000000 2016-01-01 72.160100000000000