Year	Percent of Total
1960-01-01	3.17237772932826
1961-01-01	3.19554783903137
1962-01-01	3.21221432636287
1963-01-01	3.22471171788139
1964-01-01	3.23559811245027
1965-01-01	3.24645194532053
1966-01-01	3.27162357435772
1967-01-01	3.29428279361349
1968-01-01	3.31570936967937
1969-01-01	3.33803841571415
1970-01-01	3.36345935615967
1971-01-01	3.40344718062358
1972-01-01	3.44607849299966
1973-01-01	3.48897700243266
1974-01-01	3.52802073329332
1975-01-01	3.56108963725089
1976-01-01	3.61742018431486
1977-01-01	3.66018278929881
1978-01-01	3.69292834404554
1979-01-01	3.72027423079681
1980-01-01	3.74451923180919
1981-01-01	3.77313694524360
1982-01-01	3.80077459863283
1983-01-01	3.82899720666496
1984-01-01	3.85929054698560
1985-01-01	3.89355136037742
1986-01-01	3.94363382930148
1987-01-01	3.99612675593381
1988-01-01	4.04886228532759
1989-01-01	4.09931536711804
1990-01-01	4.14659208005237
1991-01-01	4.20162050517508
1992-01-01	4.25070591761528
1993-01-01	4.29730012580685
1994-01-01	4.34530773075927
1995-01-01	4.39722507174234
1996-01-01	4.46118243515118
1997-01-01	4.52883526067299
1998-01-01	4.59938611505482
1999-01-01	4.67047381746917
2000-01-01	4.74165179559884
2001-01-01	4.82548584057214
2002-01-01	4.90780309508035
2003-01-01	4.99171442045745
2004-01-01	5.08115747053956
2005-01-01	5.17931422697886
2006-01-01	5.28917716925023
2007-01-01	5.40807018938684
2008-01-01	5.54032618566524
2009-01-01	5.69077791899764
2010-01-01	5.86336798757143
2011-01-01	6.06010182248465
2012-01-01	6.27352488376272
2013-01-01	6.50597392673689
2014-01-01	6.76051225488765
2015-01-01	7.03900418458330
2016-01-01	7.33310026989059
2017-01-01	7.64642204117894