Year	Percent of Total
1960-01-01	3.60265349475723
1961-01-01	3.63410795100536
1962-01-01	3.65364536747012
1963-01-01	3.66309490081394
1964-01-01	3.66447786485914
1965-01-01	3.65926054642622
1966-01-01	3.68152953032422
1967-01-01	3.69641921922100
1968-01-01	3.70397156572462
1969-01-01	3.70392716301764
1970-01-01	3.69653021346935
1971-01-01	3.71457856338215
1972-01-01	3.72419649210179
1973-01-01	3.72650891149099
1974-01-01	3.72234049416167
1975-01-01	3.71276062500386
1976-01-01	3.72212070104160
1977-01-01	3.72433347539447
1978-01-01	3.72012214422380
1979-01-01	3.70988788182911
1980-01-01	3.69439454448030
1981-01-01	3.69413946794647
1982-01-01	3.68599188999675
1983-01-01	3.67174049600619
1984-01-01	3.65330929785000
1985-01-01	3.63210114046505
1986-01-01	3.62292757732705
1987-01-01	3.60979907582771
1988-01-01	3.59324307138162
1989-01-01	3.57366586470820
1990-01-01	3.55210632870852
1991-01-01	3.54214906909856
1992-01-01	3.52694361826978
1993-01-01	3.50773708133182
1994-01-01	3.48586462196579
1995-01-01	3.46221831760715
1996-01-01	3.45352374288976
1997-01-01	3.43929016450832
1998-01-01	3.42051575473523
1999-01-01	3.39737243577730
2000-01-01	3.36987766456897
2001-01-01	3.36936868069893
2002-01-01	3.36185161648022
2003-01-01	3.34795300567004
2004-01-01	3.32829945207526
2005-01-01	3.30349447312824
2006-01-01	3.29493537327897
2007-01-01	3.28180610912876
2008-01-01	3.26476828062907
2009-01-01	3.24438270836531
2010-01-01	3.22150752898213
2011-01-01	3.21393583677782
2012-01-01	3.20302975237666
2013-01-01	3.18991545649728
2014-01-01	3.17587252175189
2015-01-01	3.16189233126930
2016-01-01	3.16413677964711
2017-01-01	3.16500224684516