Year Percent Change from Year Ago 1961-01-01 6.882402490386370 1962-01-01 3.838887015731770 1963-01-01 9.190422968929790 1964-01-01 9.459345518591720 1965-01-01 7.183726681940100 1966-01-01 11.983500984371900 1967-01-01 9.116916329817130 1968-01-01 13.188626102743000 1969-01-01 14.541232281683500 1970-01-01 9.997388679878490 1971-01-01 10.454545454545500 1972-01-01 7.150992003747190 1973-01-01 14.827286023138500 1974-01-01 9.460883752549280 1975-01-01 7.863519470247100 1976-01-01 13.115263046860800 1977-01-01 12.277661224117500 1978-01-01 10.774563907941900 1979-01-01 8.625626740582270 1980-01-01 -1.701335786404370 1981-01-01 7.180510839235880 1982-01-01 8.265078481397960 1983-01-01 13.242003582090800 1984-01-01 10.442864443205100 1985-01-01 7.749691530179340 1986-01-01 11.224086421602600 1987-01-01 12.467266052988500 1988-01-01 11.904718610782800 1989-01-01 7.029682000181540 1990-01-01 9.811232251654040 1991-01-01 10.353977660076500 1992-01-01 6.175462485754570 1993-01-01 6.846807734967580 1994-01-01 9.206120721744770 1995-01-01 9.570586696887830 1996-01-01 7.594526210131350 1997-01-01 5.922170675302770 1998-01-01 -5.471192097548600 1999-01-01 11.308605052850100 2000-01-01 8.924412764391050 2001-01-01 4.525319497487750 2002-01-01 7.432433613698070 2003-01-01 2.933207053036640 2004-01-01 4.899851506556580 2005-01-01 3.923687439696950 2006-01-01 5.176133981787000 2007-01-01 5.463406087622280 2008-01-01 2.829214457382720 2009-01-01 0.707518482607593 2010-01-01 6.496793585555120 2011-01-01 3.681696472321380 2012-01-01 2.292382426368980 2013-01-01 2.896212602640420 2014-01-01 3.341440519292500 2015-01-01 2.790236362682020 2016-01-01 2.929318629642630 2017-01-01 3.062755012385790