Year	Percent of Total
1960-01-01	3.31483446742228
1961-01-01	3.33583189804042
1962-01-01	3.36183713412666
1963-01-01	3.38964731285948
1964-01-01	3.41415324960724
1965-01-01	3.43301072602169
1966-01-01	3.45456306572160
1967-01-01	3.46864088474729
1968-01-01	3.47843095380134
1969-01-01	3.48829329012993
1970-01-01	3.50066163908262
1971-01-01	3.51533158566756
1972-01-01	3.53219295461466
1973-01-01	3.54970548213585
1974-01-01	3.56510553099773
1975-01-01	3.57762051660668
1976-01-01	3.61768444953160
1977-01-01	3.65277745569672
1978-01-01	3.68463319243397
1979-01-01	3.71533783054568
1980-01-01	3.74641954007573
1981-01-01	3.79061160854751
1982-01-01	3.83379245897300
1983-01-01	3.87853441540771
1984-01-01	3.92728101203250
1985-01-01	3.98253938604231
1986-01-01	4.06007441967783
1987-01-01	4.14649797127388
1988-01-01	4.24722249103453
1989-01-01	4.36932407655969
1990-01-01	4.51783413202392
1991-01-01	4.68519545280351
1992-01-01	4.86776848901683
1993-01-01	5.06219055562016
1994-01-01	5.26395806869028
1995-01-01	5.47126922891377
1996-01-01	5.67325600942900
1997-01-01	5.87741527739135
1998-01-01	6.08705906719944
1999-01-01	6.30645354377978
2000-01-01	6.53785639164230
2001-01-01	6.77942837171780
2002-01-01	7.03024592323863
2003-01-01	7.28314227543691
2004-01-01	7.52804622967479
2005-01-01	7.76165765412155
2006-01-01	7.98320659264279
2007-01-01	8.19783304377488
2008-01-01	8.41634688671374
2009-01-01	8.65008597920868
2010-01-01	8.90503964896982
2011-01-01	9.18912787521659
2012-01-01	9.49215552348426
2013-01-01	9.81906816196190
2014-01-01	10.17539968123610
2015-01-01	10.56473573209670
2016-01-01	10.95370329199290
2017-01-01	11.37292416660490