Year	Percent of Total
1960-01-01	3.23518180351729
1961-01-01	3.21762763592219
1962-01-01	3.19154345617714
1963-01-01	3.15999443313777
1964-01-01	3.12603701272602
1965-01-01	3.09150514526806
1966-01-01	3.07576495408054
1967-01-01	3.05713735255000
1968-01-01	3.03676202094641
1969-01-01	3.01567847818203
1970-01-01	2.99483548440433
1971-01-01	2.99280551697542
1972-01-01	2.98892298978498
1973-01-01	2.98289146103386
1974-01-01	2.97419457224683
1975-01-01	2.96292819537991
1976-01-01	2.95989786306008
1977-01-01	2.95377120553909
1978-01-01	2.94576312610836
1979-01-01	2.93718826110248
1980-01-01	2.92940160198871
1981-01-01	2.92611365870181
1982-01-01	2.92136828521737
1983-01-01	2.91632030087418
1984-01-01	2.91223692755468
1985-01-01	2.91027633807814
1986-01-01	2.91523384161068
1987-01-01	2.91907914438544
1988-01-01	2.92197433956248
1989-01-01	2.92328214229398
1990-01-01	2.92281111537410
1991-01-01	2.93857097559662
1992-01-01	2.95311710595169
1993-01-01	2.96862739721007
1994-01-01	2.98815074684495
1995-01-01	3.01401660358596
1996-01-01	3.02794418988961
1997-01-01	3.04022545684057
1998-01-01	3.05067286602725
1999-01-01	3.05810018265089
2000-01-01	3.06233253769146
2001-01-01	3.08056484513064
2002-01-01	3.09434260945032
2003-01-01	3.10507113344148
2004-01-01	3.11451129502579
2005-01-01	3.12401231447525
2006-01-01	3.15593374949347
2007-01-01	3.18604250485231
2008-01-01	3.21552132002504
2009-01-01	3.24520330517546
2010-01-01	3.27591523320141
2011-01-01	3.31177979643256
2012-01-01	3.34675624959156
2013-01-01	3.38187455396780
2014-01-01	3.41799240461443
2015-01-01	3.45567120594151
2016-01-01	3.50188742324558
2017-01-01	3.54808499573067