Year	Percent of Total
1960-01-01	2.74229752344629
1961-01-01	2.77171451966332
1962-01-01	2.79207843890077
1963-01-01	2.80393005813226
1964-01-01	2.80782438410839
1965-01-01	2.80438703725285
1966-01-01	2.83338632731429
1967-01-01	2.85436966197873
1968-01-01	2.86770450366991
1969-01-01	2.87314894153521
1970-01-01	2.87079652817967
1971-01-01	2.89699016889767
1972-01-01	2.91443243381818
1973-01-01	2.92426009251515
1974-01-01	2.92753041532042
1975-01-01	2.92503432260679
1976-01-01	2.93994168306540
1977-01-01	2.94985725435350
1978-01-01	2.95457539914044
1979-01-01	2.95410316193565
1980-01-01	2.94909890684182
1981-01-01	2.97313772255902
1982-01-01	2.98736997897454
1983-01-01	2.99345663527710
1984-01-01	2.99386639572173
1985-01-01	2.99006384967197
1986-01-01	3.03447381675468
1987-01-01	3.07159411347683
1988-01-01	3.09966050513311
1989-01-01	3.11379824195403
1990-01-01	3.10932905906550
1991-01-01	3.09838823952672
1992-01-01	3.07853662554470
1993-01-01	3.05203356290004
1994-01-01	3.02376072514478
1995-01-01	2.99795699407810
1996-01-01	3.01714057258660
1997-01-01	3.03232355274732
1998-01-01	3.04358228325275
1999-01-01	3.04961043497111
2000-01-01	3.04969307914178
2001-01-01	3.06586916672970
2002-01-01	3.07558264625209
2003-01-01	3.08000396417272
2004-01-01	3.08084029182721
2005-01-01	3.07934734243111
2006-01-01	3.09486086598687
2007-01-01	3.10779688492003
2008-01-01	3.11731318728023
2009-01-01	3.12206696606789
2010-01-01	3.12201129538109
2011-01-01	3.12953945035097
2012-01-01	3.13146137772259
2013-01-01	3.13063612784143
2014-01-01	3.13045730432566
2015-01-01	3.13271100666528
2016-01-01	3.14545779465433
2017-01-01	3.15830409782872