Year Percent 1973-01-01 46.638000000000005 1974-01-01 45.976700000000000 1975-01-01 43.620000000000000 1976-01-01 43.484500000000000 1977-01-01 44.356700000000000 1978-01-01 46.357600000000000 1979-01-01 47.470000000000000 1980-01-01 46.797200000000000 1981-01-01 50.395200000000000 1982-01-01 51.757800000000000 1983-01-01 51.209500000000000 1984-01-01 50.443999999999996 1985-01-01 48.701600000000000 1986-01-01 47.442500000000000 1987-01-01 49.998600000000000 1988-01-01 54.856300000000000 1989-01-01 60.512700000000000 1990-01-01 63.040600000000000 1991-01-01 59.999700000000000 1992-01-01 57.706400000000000 1993-01-01 51.791200000000000 1994-01-01 45.520800000000000 1995-01-01 41.418100000000000 1996-01-01 39.977700000000000 1997-01-01 40.488400000000000 1998-01-01 43.116000000000010 1999-01-01 43.728500000000000 2000-01-01 43.867600000000000 2001-01-01 73.067200000000000 2002-01-01 99.736700000000000 2003-01-01 99.871000000000010 2004-01-01 99.951100000000000 2005-01-01 105.339000000000000 2006-01-01 110.294000000000000 2007-01-01 115.709000000000000 2008-01-01 125.257000000000000 2009-01-01 134.094000000000000 2010-01-01 129.997000000000000 2011-01-01 132.158000000000000 2012-01-01 136.646000000000020 2013-01-01 137.822000000000000 2014-01-01 136.585000000000000 2015-01-01 133.055000000000000 2016-01-01 132.361000000000000