Year	Percent
1960-01-01	90.4427725938606
1961-01-01	90.1643555369067
1962-01-01	89.7162746268178
1963-01-01	89.2803565399070
1964-01-01	88.8450278973840
1965-01-01	88.4702332099442
1966-01-01	88.2818033892853
1967-01-01	88.2714079881994
1968-01-01	87.8188546269781
1969-01-01	87.5112449263564
1970-01-01	87.2838869019024
1971-01-01	86.7587418716034
1972-01-01	86.5961619173503
1973-01-01	86.5989382113269
1974-01-01	86.5532821276800
1975-01-01	85.7277231764773
1976-01-01	85.5372097179053
1977-01-01	85.7978443844346
1978-01-01	86.0074986051448
1979-01-01	86.1005319998094
1980-01-01	85.7970736484738
1981-01-01	85.4508409398364
1982-01-01	85.1758014842578
1983-01-01	85.0546957104735
1984-01-01	85.2527565884296
1985-01-01	85.3859893991214
1986-01-01	85.4376373182983
1987-01-01	85.4392497943413
1988-01-01	85.4846362455975
1989-01-01	85.8758220207062
1990-01-01	85.5919470675740
1991-01-01	85.0929617164428
1992-01-01	85.1838782969202
1993-01-01	84.8789519098536
1994-01-01	84.2863633570917
1995-01-01	84.2906861232014
1996-01-01	84.2664075297552
1997-01-01	84.2325129352304
1998-01-01	84.2314869294242
1999-01-01	83.9849265002117
2000-01-01	83.9231535367574
2001-01-01	83.4479984915927
2002-01-01	82.9612929562119
2003-01-01	82.1691513958246
2004-01-01	81.9044001053561
2005-01-01	81.8120718101244
2006-01-01	81.9392341804590
2007-01-01	81.6864954418669
2008-01-01	81.4367523393523
2009-01-01	80.3571962322151
2010-01-01	79.5533526891417
2011-01-01	78.8967473636478
2012-01-01	78.8323797176519
2013-01-01	78.6586019391564
2014-01-01	78.4672218147925
2015-01-01	78.4745281274424
2016-01-01	78.7865357420384
2017-01-01	78.9679907330726