Year	Percent of Total
1960-01-01	3.58417115627682
1961-01-01	3.54867276910847
1962-01-01	3.50343765512232
1963-01-01	3.45226347109349
1964-01-01	3.39983307118992
1965-01-01	3.34929722183957
1966-01-01	3.34535802675210
1967-01-01	3.33691687256272
1968-01-01	3.32705749386215
1969-01-01	3.31953397068344
1970-01-01	3.31611468232882
1971-01-01	3.34824211509713
1972-01-01	3.37914790719503
1973-01-01	3.40751102333925
1974-01-01	3.43141652487179
1975-01-01	3.45026929423083
1976-01-01	3.49532190305117
1977-01-01	3.53336816433315
1978-01-01	3.56273309139071
1979-01-01	3.58088790306391
1980-01-01	3.58746756101661
1981-01-01	3.61020193293312
1982-01-01	3.62203306124836
1983-01-01	3.62709660541282
1984-01-01	3.62999278087468
1985-01-01	3.63402472384526
1986-01-01	3.66076833102215
1987-01-01	3.68657190099207
1988-01-01	3.71411255927369
1989-01-01	3.74619102298341
1990-01-01	3.78464964396615
1991-01-01	3.85738874748215
1992-01-01	3.92990084482030
1993-01-01	4.00289506171911
1994-01-01	4.07734043653304
1995-01-01	4.15406902621078
1996-01-01	4.26615271980497
1997-01-01	4.37765752117210
1998-01-01	4.48925288795873
1999-01-01	4.60026816410801
2000-01-01	4.70920525551170
2001-01-01	4.76848669137311
2002-01-01	4.80620674381541
2003-01-01	4.82053988258389
2004-01-01	4.81305945211130
2005-01-01	4.78891105938339
2006-01-01	4.83961495661196
2007-01-01	4.87275370486043
2008-01-01	4.88719401392474
2009-01-01	4.88018161307424
2010-01-01	4.84970148722072
2011-01-01	4.90130763646049
2012-01-01	4.94148677722089
2013-01-01	4.98025127838494
2014-01-01	5.02918193639697
2015-01-01	5.09506791959051
2016-01-01	5.20159442419219
2017-01-01	5.31947749702842