Year	Percent of Total
1960-01-01	5.78309225143316
1961-01-01	5.87074129791397
1962-01-01	5.95819527583220
1963-01-01	6.05255784732526
1964-01-01	6.15896478837087
1965-01-01	6.28087950844783
1966-01-01	6.43497807871257
1967-01-01	6.59851433613580
1968-01-01	6.77153278076389
1969-01-01	6.95019742136748
1970-01-01	7.13170941571101
1971-01-01	7.33572317932437
1972-01-01	7.52155874484966
1973-01-01	7.69912301216632
1974-01-01	7.88516101952875
1975-01-01	8.08405982843159
1976-01-01	8.28488919117190
1977-01-01	8.49995886250005
1978-01-01	8.69840741327747
1979-01-01	8.83183975307834
1980-01-01	8.88443085124936
1981-01-01	8.87901112031171
1982-01-01	8.80470156652012
1983-01-01	8.69551982823442
1984-01-01	8.59540977395605
1985-01-01	8.52892191095946
1986-01-01	8.52712980580401
1987-01-01	8.53752142028121
1988-01-01	8.57749150967594
1989-01-01	8.66930327769990
1990-01-01	8.82149311917323
1991-01-01	9.03011290960785
1992-01-01	9.35118131431518
1993-01-01	9.62638182621824
1994-01-01	9.84999866543662
1995-01-01	9.94572716422745
1996-01-01	10.06315837891550
1997-01-01	10.09170476055710
1998-01-01	10.07547154902450
1999-01-01	10.08870775849040
2000-01-01	10.15583155309730
2001-01-01	10.31922711128140
2002-01-01	10.52992389489890
2003-01-01	10.73380793514920
2004-01-01	10.84658495614570
2005-01-01	10.82634907034010
2006-01-01	10.78358795624380
2007-01-01	10.65510019633180
2008-01-01	10.49165794321930
2009-01-01	10.35621510171060
2010-01-01	10.27580747933140
2011-01-01	10.28139584401210
2012-01-01	10.30993013647410
2013-01-01	10.35548540867040
2014-01-01	10.42854801497530