Year Percent 1960-01-01 -5.0300415959369000 1961-01-01 3.7797063834267600 1962-01-01 -0.5549042598695240 1963-01-01 4.3068217543595600 1964-01-01 9.1621458712944200 1965-01-01 2.2639425728972700 1966-01-01 8.3018358533230600 1967-01-01 -2.9353109810065500 1968-01-01 1.3162118782735800 1969-01-01 1.4131812420197600 1970-01-01 1.3684934073666500 1971-01-01 9.5795832822563400 1972-01-01 3.1896939691793000 1973-01-01 22.7389194789195000 1974-01-01 14.9506973439721000 1975-01-01 16.7735703245817000 1976-01-01 7.0381522782362000 1977-01-01 6.4919005811333400 1978-01-01 -2.6735949836929400 1979-01-01 13.0939242998194000 1980-01-01 17.7783052456577000 1981-01-01 10.8583333329997000 1982-01-01 7.3592422760505000 1983-01-01 10.2436633526545000 1984-01-01 6.4020323910607600 1985-01-01 10.6488390138928000 1986-01-01 3.2799266336661900 1987-01-01 -11.4494646121705000 1988-01-01 4.1054680587505900 1989-01-01 6.9239050371123900 1990-01-01 21.2760320067832000 1991-01-01 15.4199073669492000 1992-01-01 19.3584946541220000 1993-01-01 29.7059715065173000 1994-01-01 39.3316195372753000 1995-01-01 27.6081851727601000 1996-01-01 20.5835962145112000 1997-01-01 20.5590073395833000 1998-01-01 10.6343381981750000 1999-01-01 8.6709571968534500 2000-01-01 13.7077215213675000 2001-01-01 14.1732804232802000 2002-01-01 9.8534437814981400 2003-01-01 39.2814455459465000 2004-01-01 22.8117112569410000 2005-01-01 15.7286461900051000 2006-01-01 13.0657120940936000 2007-01-01 8.5287846481877200 2008-01-01 15.5196761326427000 2009-01-01 -0.0146362781799481 2010-01-01 5.6965110233999600 2011-01-01 8.4014667170682700 2012-01-01 6.2890818300418300 2013-01-01 5.8534727218859800 2014-01-01 4.5661735305877600 2015-01-01 9.0165188130926900 2016-01-01 13.8337425464749000 2017-01-01 14.6730757379676000