Year	Percent of Total
1960-01-01	3.50114168447461
1961-01-01	3.53149349420589
1962-01-01	3.55550600754880
1963-01-01	3.57169252740266
1964-01-01	3.57904543681756
1965-01-01	3.57799172599872
1966-01-01	3.60950292920524
1967-01-01	3.63209283170814
1968-01-01	3.64848983885383
1969-01-01	3.66111306720746
1970-01-01	3.67149812462712
1971-01-01	3.71247349132174
1972-01-01	3.74608188344826
1973-01-01	3.77260304002358
1974-01-01	3.79264710473094
1975-01-01	3.80692259242215
1976-01-01	3.84735214520761
1977-01-01	3.88108259597464
1978-01-01	3.90650539460264
1979-01-01	3.92096269110052
1980-01-01	3.92408171413898
1981-01-01	3.94229958517224
1982-01-01	3.94715185138887
1983-01-01	3.94391387445758
1984-01-01	3.93864037258918
1985-01-01	3.93514460917827
1986-01-01	3.95615881605056
1987-01-01	3.97544094995270
1988-01-01	3.99393185878417
1989-01-01	4.01228804193238
1990-01-01	4.02894064198947
1991-01-01	4.08156298545501
1992-01-01	4.13160283276699
1993-01-01	4.17735774647418
1994-01-01	4.21647114215688
1995-01-01	4.24971996275485
1996-01-01	4.31078731688524
1997-01-01	4.36305127649638
1998-01-01	4.41035866550242
1999-01-01	4.45644415313455
2000-01-01	4.50338655851769
2001-01-01	4.56795707317726
2002-01-01	4.62769208337067
2003-01-01	4.68017908618422
2004-01-01	4.72154132925715
2005-01-01	4.75115087081579
2006-01-01	4.80395051120354
2007-01-01	4.84573036079543
2008-01-01	4.87962017988380
2009-01-01	4.90938205576073
2010-01-01	4.93803844518472
2011-01-01	4.99395263454501
2012-01-01	5.04750211981446
2013-01-01	5.10392332334756
2014-01-01	5.16936075299760
2015-01-01	5.24893354198510
2016-01-01	5.36240138218170
2017-01-01	5.48266314622819