Year	Percent of Total
1960-01-01	3.87358628606125
1961-01-01	3.91433149495298
1962-01-01	3.96145733471932
1963-01-01	4.01152956243330
1964-01-01	4.05775950611986
1965-01-01	4.09782185262297
1966-01-01	4.13687893752010
1967-01-01	4.16739142081454
1968-01-01	4.19240837002224
1969-01-01	4.21730817463899
1970-01-01	4.24508763028810
1971-01-01	4.27641207959696
1972-01-01	4.30873486740150
1973-01-01	4.34047453020184
1974-01-01	4.36785407617583
1975-01-01	4.38896876372082
1976-01-01	4.41597841524335
1977-01-01	4.43323466453139
1978-01-01	4.44320992518567
1979-01-01	4.44902664825005
1980-01-01	4.45229070443139
1981-01-01	4.46170254729545
1982-01-01	4.46878391845384
1983-01-01	4.47415456507252
1984-01-01	4.47764471146516
1985-01-01	4.47998341200580
1986-01-01	4.48444682763734
1987-01-01	4.48377253262145
1988-01-01	4.48286749172681
1989-01-01	4.48919629487061
1990-01-01	4.50709661698299
1991-01-01	4.54689247535292
1992-01-01	4.59648598789890
1993-01-01	4.65031260974495
1994-01-01	4.70011998416852
1995-01-01	4.74227123525918
1996-01-01	4.80031896038307
1997-01-01	4.84222964821592
1998-01-01	4.87167661827465
1999-01-01	4.89255604789416
2000-01-01	4.90618056925252
2001-01-01	4.92168833871004
2002-01-01	4.92782364673935
2003-01-01	4.92368394438740
2004-01-01	4.90633699742693
2005-01-01	4.87655804257537
2006-01-01	4.85208187284983
2007-01-01	4.81699814299596
2008-01-01	4.78327901289871
2009-01-01	4.76603765412201
2010-01-01	4.77272531095463
2011-01-01	4.83038860672656
2012-01-01	4.89472335595069
2013-01-01	4.95886348293687
2014-01-01	5.01572410033720
2015-01-01	5.06322196171621
2016-01-01	5.11020211470989
2017-01-01	5.15900608889609