"date","value"
1980-01-01,0.82989428
1981-01-01,0.85951092
1982-01-01,0.87668916
1983-01-01,0.86670716
1984-01-01,0.932052
1985-01-01,1.04826364
1986-01-01,1.3111932
1987-01-01,1.63756228
1988-01-01,2.0641074
1989-01-01,1.91268276
1990-01-01,2.03544572
1991-01-01,2.17721128
1992-01-01,2.38968344
1993-01-01,2.75059208
1994-01-01,3.0906664
1995-01-01,3.42664028
1996-01-01,3.83064908
1997-01-01,3.97190864
1998-01-01,3.83160036
1999-01-01,4.143101
2000-01-01,4.566551
2001-01-01,4.47541
2002-01-01,4.462796
2003-01-01,4.384829
2004-01-01,4.796861
2005-01-01,5.046211
2006-01-01,5.098759
2007-01-01,5.196519
2008-01-01,5.166843
2009-01-01,5.174744
2010-01-01,5.440894