Year	Percent of Total
1960-01-01	4.61535163418099
1961-01-01	4.64011413272891
1962-01-01	4.66205887558055
1963-01-01	4.67695502736916
1964-01-01	4.68541118031779
1965-01-01	4.69062442844543
1966-01-01	4.74520483824067
1967-01-01	4.80111058965844
1968-01-01	4.85917358503953
1969-01-01	4.91562058380710
1970-01-01	4.96940625077804
1971-01-01	5.01201641724309
1972-01-01	5.04259462481912
1973-01-01	5.06397002235025
1974-01-01	5.07900931773435
1975-01-01	5.08826239512513
1976-01-01	5.12896529308304
1977-01-01	5.16076728358077
1978-01-01	5.18276612586980
1979-01-01	5.18670781737173
1980-01-01	5.16975963961376
1981-01-01	5.16973385051404
1982-01-01	5.15140313992023
1983-01-01	5.12236938870832
1984-01-01	5.09114823943081
1985-01-01	5.06414753836401
1986-01-01	5.05244106571334
1987-01-01	5.04712828938128
1988-01-01	5.04964151706102
1989-01-01	5.05845049960662
1990-01-01	5.07191792019283
1991-01-01	5.11396473816600
1992-01-01	5.14578562444124
1993-01-01	5.17136864495034
1994-01-01	5.19659244285004
1995-01-01	5.22064518347497
1996-01-01	5.26691684051710
1997-01-01	5.30910704146810
1998-01-01	5.34697217814780
1999-01-01	5.38609843807952
2000-01-01	5.42259767178139
2001-01-01	5.45922451943137
2002-01-01	5.49190585863418
2003-01-01	5.51815717766812
2004-01-01	5.53350770016902
2005-01-01	5.53602070041819
2006-01-01	5.54607234532480
2007-01-01	5.54382864713276
2008-01-01	5.53739485977534
2009-01-01	5.53569287488346
2010-01-01	5.54541573105534
2011-01-01	5.57003261446671
2012-01-01	5.60485138900048
2013-01-01	5.64999337492114
2014-01-01	5.70491773831702
2015-01-01	5.77045422556508
2016-01-01	5.85741998048433
2017-01-01	5.94894276796463