Year	Percent of Total
1960-01-01	2.94777011355634
1961-01-01	2.97256790059113
1962-01-01	2.98838602480104
1963-01-01	2.99570226507377
1964-01-01	2.99578957367316
1965-01-01	2.98829452518555
1966-01-01	3.00622668087237
1967-01-01	3.01587218149036
1968-01-01	3.01785188193954
1969-01-01	3.01251299844063
1970-01-01	3.00196260800566
1971-01-01	3.07543438092926
1972-01-01	3.14338382081276
1973-01-01	3.20551405760530
1974-01-01	3.25848363379608
1975-01-01	3.29778558810119
1976-01-01	3.30637098195317
1977-01-01	3.30477855874368
1978-01-01	3.29572422279501
1979-01-01	3.28170512619259
1980-01-01	3.26283631261725
1981-01-01	3.26179586782045
1982-01-01	3.25685272440535
1983-01-01	3.24555693222872
1984-01-01	3.22565261637191
1985-01-01	3.19782835885332
1986-01-01	3.18394981787914
1987-01-01	3.16398061164424
1988-01-01	3.14044746489261
1989-01-01	3.11591386705818
1990-01-01	3.09145282494509
1991-01-01	3.07411628336673
1992-01-01	3.05120577325517
1993-01-01	3.02344423309569
1994-01-01	2.99153196050076
1995-01-01	2.95622753082912
1996-01-01	2.98814191824287
1997-01-01	3.01513539461170
1998-01-01	3.03434075526255
1999-01-01	3.04164397175319
2000-01-01	3.03360285568498
2001-01-01	3.01571319203109
2002-01-01	2.98949695538235
2003-01-01	2.95605723652125
2004-01-01	2.91626075834002
2005-01-01	2.87087031099018
2006-01-01	2.83291758617015
2007-01-01	2.79172444160410
2008-01-01	2.74827988968694
2009-01-01	2.70319427505919
2010-01-01	2.65850189290892
2011-01-01	2.61493659318928
2012-01-01	2.57099201584599
2013-01-01	2.53306550518917
2014-01-01	2.50890890324198
2015-01-01	2.50248302084365
2016-01-01	2.52767999443564
2017-01-01	2.56235016791319