Year Percent Change 1971-01-01 9.737087832170380 1972-01-01 12.148621428482000 1973-01-01 15.284062438095500 1974-01-01 27.029215222928800 1975-01-01 17.798284384282500 1976-01-01 15.612454351824600 1977-01-01 15.804934051620200 1978-01-01 22.065266899546700 1979-01-01 21.048886325339500 1980-01-01 20.536362342227300 1981-01-01 22.353394868579600 1982-01-01 7.525980090223570 1983-01-01 13.182253406998200 1984-01-01 5.177630701872020 1985-01-01 2.983226957349480 1986-01-01 3.447758400744690 1987-01-01 3.352907132898020 1988-01-01 5.144607251118650 1989-01-01 3.004543627536350 1990-01-01 6.795862093685090 1991-01-01 13.847602237754400 1992-01-01 9.144890713051840 1993-01-01 8.783314709898590 1994-01-01 8.971765823818640 1995-01-01 9.416560826946440 1996-01-01 6.987631767216700 1997-01-01 -1.022153847412400 1998-01-01 0.417583718744766 1999-01-01 0.893890190485739 2000-01-01 -0.646423407214643 2001-01-01 1.194003480649540 2002-01-01 0.312145861779235 2003-01-01 3.679923177534960 2004-01-01 2.036297117693610 2005-01-01 0.980624760612557 2006-01-01 0.396498393245026 2007-01-01 1.025158105919870 2008-01-01 4.486745157940680 2009-01-01 3.409411178295220 2010-01-01 0.867404601233278