Year Percent 1966-01-01 2.47900839657731000 1967-01-01 3.20717908718530000 1968-01-01 3.96945410534388000 1969-01-01 2.25438149968916000 1970-01-01 13.39876253481820000 1971-01-01 8.39134524920583000 1972-01-01 7.88057628905349000 1973-01-01 13.44060069717410000 1974-01-01 34.22060422687920000 1975-01-01 17.74278769965230000 1976-01-01 9.66911984668740000 1977-01-01 8.86573190026191000 1978-01-01 10.87751829209910000 1979-01-01 9.39004271287360000 1980-01-01 19.47772911329120000 1981-01-01 15.12484437703460000 1982-01-01 4.61406749873086000 1983-01-01 1.47305853462303000 1984-01-01 1.20548410365589000 1985-01-01 1.42319898238732000 1986-01-01 2.19025825433131000 1987-01-01 7.02175303902782000 1988-01-01 0.82947242564639200 1989-01-01 4.37263766397329000 1990-01-01 4.26755662855972000 1991-01-01 6.14955053119051000 1992-01-01 5.13889779944826000 1993-01-01 0.84818159628960600 1994-01-01 2.81591665153970000 1995-01-01 5.62965921512375000 1996-01-01 0.92484260961599200 1997-01-01 -0.00552028705472678 1998-01-01 3.20194341679090000 1999-01-01 3.50379784108943000 2000-01-01 3.71078608713611000 2001-01-01 5.30722081028545000 2002-01-01 -0.25553662691644200 2003-01-01 1.03425372426237000 2004-01-01 1.46036814425232000 2005-01-01 3.91076965798121000 2006-01-01 2.33832175307319000 2007-01-01 2.82310373736930000 2008-01-01 5.54954769383937000 2009-01-01 -0.15693608716865700 2010-01-01 3.25034409180126000 2011-01-01 2.76940794144093000 2012-01-01 4.17763587102517000 2013-01-01 1.47201838917869000 2014-01-01 3.51847818195019000 2015-01-01 -0.98430920351251700 2016-01-01 -3.09298958876075000 2017-01-01 0.11841772577107600