Year Percent Change 1971-01-01 6.394291100051430 1972-01-01 11.735923433691600 1973-01-01 13.923739779199300 1974-01-01 21.861129860201900 1975-01-01 15.485864872220800 1976-01-01 23.404105850839200 1977-01-01 19.072589286811100 1978-01-01 17.074160584167900 1979-01-01 22.361532906178700 1980-01-01 28.566827398219200 1981-01-01 14.130993057627400 1982-01-01 6.292904243694700 1983-01-01 5.782313947379860 1984-01-01 0.596793565615141 1985-01-01 0.522226110818255 1986-01-01 2.835336876726190 1987-01-01 3.900205215969400 1988-01-01 13.563075535555800 1989-01-01 2.982007106021470 1990-01-01 4.265805677294030 1991-01-01 11.405711154728700 1992-01-01 6.010494800341370 1993-01-01 3.657658576575920 1994-01-01 5.928422829119910 1995-01-01 9.844458659784850 1996-01-01 6.270563156130570 1997-01-01 -4.067869048448010 1998-01-01 -2.892372821795620 1999-01-01 -10.969718611044900 2000-01-01 -2.304924694334640 2001-01-01 5.081220950746130 2002-01-01 1.613079619202750 2003-01-01 -1.172553064385040 2004-01-01 2.475054510155320 2005-01-01 3.891831198081860 2006-01-01 -1.523146563667610 2007-01-01 -0.398566400295184 2008-01-01 0.666099031172702 2009-01-01 2.255191245999130 2010-01-01 -2.726345788694870