Year	Percent of Total
1960-01-01	4.13669188801446
1961-01-01	4.07226313600816
1962-01-01	4.03521715285576
1963-01-01	4.02094567097365
1964-01-01	4.01582677238488
1965-01-01	4.00550945921101
1966-01-01	3.99111197099079
1967-01-01	3.96891241935162
1968-01-01	3.94209038370125
1969-01-01	3.90952110956036
1970-01-01	3.87585415583681
1971-01-01	3.90904479863025
1972-01-01	3.92622076676972
1973-01-01	3.92350628760072
1974-01-01	3.90688552967825
1975-01-01	3.88469450219769
1976-01-01	4.01810916416688
1977-01-01	4.14548959542215
1978-01-01	4.25610791878425
1979-01-01	4.34076630997584
1980-01-01	4.39829426893105
1981-01-01	4.42964288171747
1982-01-01	4.44054368846695
1983-01-01	4.44702983848891
1984-01-01	4.46880269814502
1985-01-01	4.51665006595418
1986-01-01	4.52679592535298
1987-01-01	4.56426884640848
1988-01-01	4.61865500228672
1989-01-01	4.67418621649495
1990-01-01	4.72277849766364
1991-01-01	4.80520981850411
1992-01-01	4.87554492706315
1993-01-01	4.93838930887664
1994-01-01	5.00712754297691
1995-01-01	5.08581911278182
1996-01-01	5.19047365099681
1997-01-01	5.28255043271909
1998-01-01	5.35878325678135
1999-01-01	5.42137844938898
2000-01-01	5.47513706894727
2001-01-01	5.57332440239461
2002-01-01	5.67381025331026
2003-01-01	5.77025466281137
2004-01-01	5.85337195875453
2005-01-01	5.91907741519122
2006-01-01	5.99039870555039
2007-01-01	6.04624243434928
2008-01-01	6.09417099551973
2009-01-01	6.14652941978683
2010-01-01	6.20943047274013
2011-01-01	6.29396018352524
2012-01-01	6.38400080435394
2013-01-01	6.47786338334501
2014-01-01	6.57677651078244
2015-01-01	6.67976601929112
2016-01-01	6.80339847555734
2017-01-01	6.93306023052811