Year	Percent of Total
1960-01-01	2.39131294245122
1961-01-01	2.40601560698920
1962-01-01	2.41865599768766
1963-01-01	2.42822826309603
1964-01-01	2.43323529814972
1965-01-01	2.43439215547427
1966-01-01	2.45983014556345
1967-01-01	2.47587200109613
1968-01-01	2.48373072927690
1969-01-01	2.48484432047407
1970-01-01	2.47968386118712
1971-01-01	2.50148601952154
1972-01-01	2.51735743192684
1973-01-01	2.52793790362489
1974-01-01	2.53430867667693
1975-01-01	2.53822265724530
1976-01-01	2.56682514801259
1977-01-01	2.58765305611739
1978-01-01	2.60123642872533
1979-01-01	2.60686013930538
1980-01-01	2.60320562027797
1981-01-01	2.62166176977865
1982-01-01	2.63628312621767
1983-01-01	2.64802597702841
1984-01-01	2.65862886334494
1985-01-01	2.67023365733927
1986-01-01	2.69494065152374
1987-01-01	2.71603718484556
1988-01-01	2.73451817620256
1989-01-01	2.75075499474001
1990-01-01	2.76516824283955
1991-01-01	2.81459228004309
1992-01-01	2.86026368329654
1993-01-01	2.90228020979802
1994-01-01	2.94045244098440
1995-01-01	2.97496483839024
1996-01-01	2.99012406194765
1997-01-01	2.99808982002874
1998-01-01	3.00110431661497
1999-01-01	3.00155669466379
2000-01-01	3.00100397269895
2001-01-01	3.07791760773633
2002-01-01	3.15498158500365
2003-01-01	3.23003394861842
2004-01-01	3.29962981980447
2005-01-01	3.36119532769669
2006-01-01	3.41284988643776
2007-01-01	3.44821449244615
2008-01-01	3.47152022607328
2009-01-01	3.49054927639005
2010-01-01	3.51029026312878
2011-01-01	3.48063490365100
2012-01-01	3.45849028616858
2013-01-01	3.43897505569198
2014-01-01	3.41556920979656
2015-01-01	3.38640126765859
2016-01-01	3.38838662889223
2017-01-01	3.38451327094484