Year Percent 1960-01-01 2.3501614137704800 1961-01-01 2.0506973127869100 1962-01-01 4.6911436074047400 1963-01-01 7.4547182253910700 1964-01-01 5.9123225321858100 1965-01-01 4.5192683074346700 1966-01-01 2.3465889341331900 1967-01-01 3.7333383207382300 1968-01-01 1.2773133539079600 1969-01-01 2.6572527338696700 1970-01-01 4.9683198732933700 1971-01-01 4.7916643833378500 1972-01-01 5.7495039373001500 1973-01-01 10.7986174547601000 1974-01-01 19.1597695854699000 1975-01-01 16.9505025668306000 1976-01-01 16.6141664725788000 1977-01-01 17.1300487866500000 1978-01-01 12.0940138425074000 1979-01-01 14.7985735661485000 1980-01-01 21.0641682770745000 1981-01-01 17.9692987519672000 1982-01-01 16.4804146202215000 1983-01-01 14.6465766748770000 1984-01-01 10.7944960076810000 1985-01-01 9.2059914425311900 1986-01-01 5.8235469186201800 1987-01-01 4.7472849038979000 1988-01-01 5.0582474766712100 1989-01-01 6.2598313795697300 1990-01-01 6.4566090614640500 1991-01-01 6.2499992979029100 1992-01-01 5.2705899859293200 1993-01-01 4.6267346833129300 1994-01-01 4.0518421806572000 1995-01-01 5.2354225804429900 1996-01-01 4.0069766898103900 1997-01-01 2.0431077975013300 1998-01-01 1.9550855771938300 1999-01-01 1.6634599500771400 2000-01-01 2.5376853209500500 2001-01-01 2.7851654271355500 2002-01-01 2.4653231917116400 2003-01-01 2.6725555277285200 2004-01-01 2.2067366142365400 2005-01-01 1.9852929852798300 2006-01-01 2.0908439101275500 2007-01-01 1.8297411220240000 2008-01-01 3.3478325840102300 2009-01-01 0.7747681313873840 2010-01-01 1.5255160211824800 2011-01-01 2.7806327287932400 2012-01-01 3.0413633322677300 2013-01-01 1.2199934227430500 2014-01-01 0.2410474298267730 2015-01-01 0.0387903996579552 2016-01-01 -0.0940166569157271 2017-01-01 1.2265331664580800