Year	Percent of Total
1960-01-01	2.63083961111888
1961-01-01	2.66107460016886
1962-01-01	2.68506528197688
1963-01-01	2.70466172416119
1964-01-01	2.72330431620914
1965-01-01	2.74209009313890
1966-01-01	2.77651609675587
1967-01-01	2.80928084262923
1968-01-01	2.83650076295063
1969-01-01	2.85341977110287
1970-01-01	2.85899940801794
1971-01-01	2.87413847984943
1972-01-01	2.87924044279901
1973-01-01	2.87825598367114
1974-01-01	2.87627097581686
1975-01-01	2.87674579963592
1976-01-01	2.89993626513703
1977-01-01	2.92288127025344
1978-01-01	2.94301653353824
1979-01-01	2.95846763610931
1980-01-01	2.96933091818050
1981-01-01	2.99502255946839
1982-01-01	3.01691000139912
1983-01-01	3.03767888563349
1984-01-01	3.06137204044762
1985-01-01	3.09083914437516
1986-01-01	3.14179928338858
1987-01-01	3.19541091510837
1988-01-01	3.25048981772843
1989-01-01	3.30564230677650
1990-01-01	3.36027940114940
1991-01-01	3.43830767235352
1992-01-01	3.50945517680097
1993-01-01	3.57360908256338
1994-01-01	3.63186407160546
1995-01-01	3.68501134026274
1996-01-01	3.75533241648988
1997-01-01	3.82355799248946
1998-01-01	3.88663907247145
1999-01-01	3.94051989764299
2000-01-01	3.98399484050073
2001-01-01	4.03311679566515
2002-01-01	4.07292317833755
2003-01-01	4.10585099225806
2004-01-01	4.13587639218015
2005-01-01	4.16561418469783
2006-01-01	4.18714387570717
2007-01-01	4.21287555602854
2008-01-01	4.24055033261304
2009-01-01	4.26661864650192
2010-01-01	4.29049288205524
2011-01-01	4.32449329613733
2012-01-01	4.35323529689106
2013-01-01	4.38592981604382
2014-01-01	4.43530243458764
2015-01-01	4.50732010581311
2016-01-01	4.59094481045012
2017-01-01	4.69395961321555