Year	Percent of Total
1960-01-01	3.79138489400931
1961-01-01	3.82223134456181
1962-01-01	3.83068076763231
1963-01-01	3.82318371492144
1964-01-01	3.80849467455831
1965-01-01	3.79005730800774
1966-01-01	3.83736386670327
1967-01-01	3.88351023435581
1968-01-01	3.92667058903508
1969-01-01	3.96433804183593
1970-01-01	3.99682157654223
1971-01-01	4.05576739974857
1972-01-01	4.10774091081691
1973-01-01	4.15453989347451
1974-01-01	4.19968697066128
1975-01-01	4.24532261864255
1976-01-01	4.31769697122866
1977-01-01	4.38781465316158
1978-01-01	4.45199949625204
1979-01-01	4.50412841829018
1980-01-01	4.54185831750276
1981-01-01	4.59103606933338
1982-01-01	4.62250403510666
1983-01-01	4.64291238214582
1984-01-01	4.65992464796869
1985-01-01	4.67771370659138
1986-01-01	4.71213629657473
1987-01-01	4.74290424073112
1988-01-01	4.77394450368253
1989-01-01	4.81073583558480
1990-01-01	4.85546576421295
1991-01-01	4.92512451165261
1992-01-01	5.00483979998968
1993-01-01	5.08827764343280
1994-01-01	5.16590105891003
1995-01-01	5.23441217721513
1996-01-01	5.33312765839072
1997-01-01	5.41382574980194
1998-01-01	5.48547876446870
1999-01-01	5.55904458420384
2000-01-01	5.63933972072527
2001-01-01	5.74088759132961
2002-01-01	5.84415491079746
2003-01-01	5.94360684442511
2004-01-01	6.02757607775956
2005-01-01	6.09197111938959
2006-01-01	6.16465044091908
2007-01-01	6.22282773596972
2008-01-01	6.27455299529069
2009-01-01	6.33015050866093
2010-01-01	6.39558292485149
2011-01-01	6.48843172622838
2012-01-01	6.58352582666181
2013-01-01	6.69002481754648
2014-01-01	6.82114064143802
2015-01-01	6.98518559786136
2016-01-01	7.19518623823215
2017-01-01	7.43244947468449