Year	Percent of Total
1960-01-01	2.33162735376312
1961-01-01	2.39311646760294
1962-01-01	2.44411355221411
1963-01-01	2.48483388728437
1964-01-01	2.51568478629663
1965-01-01	2.53731977808138
1966-01-01	2.60535659352294
1967-01-01	2.66242736550254
1968-01-01	2.70827916094119
1969-01-01	2.74322045579607
1970-01-01	2.76814351242755
1971-01-01	2.83189254742957
1972-01-01	2.88533919936798
1973-01-01	2.92856416585293
1974-01-01	2.96137062645767
1975-01-01	2.98368116570762
1976-01-01	3.04645956024805
1977-01-01	3.09646839669414
1978-01-01	3.13435420580482
1979-01-01	3.16093935298822
1980-01-01	3.17690147640800
1981-01-01	3.22472212519112
1982-01-01	3.26448275452607
1983-01-01	3.29546561357217
1984-01-01	3.31675705016517
1985-01-01	3.32831386299033
1986-01-01	3.33906465184510
1987-01-01	3.33993319224533
1988-01-01	3.33104165058600
1989-01-01	3.31195643546493
1990-01-01	3.28290641030326
1991-01-01	3.25588138187447
1992-01-01	3.21771930705801
1993-01-01	3.17029846502624
1994-01-01	3.11466672534286
1995-01-01	3.05209835044586
1996-01-01	3.00602203177655
1997-01-01	2.95211328140163
1998-01-01	2.89258805308621
1999-01-01	2.82962386400207
2000-01-01	2.76487425591892
2001-01-01	2.73048369106441
2002-01-01	2.69229893192116
2003-01-01	2.65137928666532
2004-01-01	2.60902651296348
2005-01-01	2.56583069647957
2006-01-01	2.55246570349053
2007-01-01	2.53639817117867
2008-01-01	2.51729678279908
2009-01-01	2.49439621258668
2010-01-01	2.46791185281179
2011-01-01	2.46120732967937
2012-01-01	2.45092454289414
2013-01-01	2.43797079118545
2014-01-01	2.42327736468665
2015-01-01	2.40787396392306
2016-01-01	2.40975311471100
2017-01-01	2.40862709865307