Year Percent 1960-01-01 43.13370000000000 1961-01-01 38.67060000000000 1962-01-01 48.74600000000000 1963-01-01 61.28040000000000 1964-01-01 61.67920000000000 1965-01-01 65.46520000000000 1966-01-01 65.94970000000000 1967-01-01 64.45980000000000 1968-01-01 62.90000000000000 1969-01-01 62.47350000000000 1970-01-01 75.15710000000000 1971-01-01 98.07470000000000 1972-01-01 106.37500000000000 1973-01-01 105.90500000000000 1974-01-01 106.36200000000001 1975-01-01 108.96900000000000 1976-01-01 113.36100000000000 1977-01-01 117.33000000000000 1978-01-01 121.40000000000000 1979-01-01 125.12000000000000 1980-01-01 130.23200000000000 1981-01-01 133.58600000000000 1982-01-01 140.10000000000000 1983-01-01 146.85700000000000 1984-01-01 150.01600000000000 1985-01-01 151.42500000000000 1986-01-01 157.52700000000002 1987-01-01 165.36700000000002 1988-01-01 167.62400000000002 1989-01-01 171.67300000000000 1990-01-01 173.31400000000002 1991-01-01 173.50900000000001 1992-01-01 176.51300000000000 1993-01-01 182.35600000000000 1994-01-01 187.26200000000000 1995-01-01 190.19700000000000 1996-01-01 192.43500000000000 1997-01-01 199.38900000000000 1998-01-01 209.51700000000000 1999-01-01 218.64000000000000 2000-01-01 219.79700000000000 2001-01-01 201.88500000000000 2002-01-01 183.95400000000000 2003-01-01 185.30599999999998 2004-01-01 184.42500000000000 2005-01-01 183.74099999999999 2006-01-01 182.90900000000002 2007-01-01 180.41900000000000 2008-01-01 187.11599999999999 2009-01-01 200.40900000000002 2010-01-01 200.17900000000000 2011-01-01 208.45100000000000 2012-01-01 212.44200000000000 2013-01-01 213.92100000000000 2014-01-01 217.56500000000000 2015-01-01 215.52700000000002 2016-01-01 218.22500000000000