Year	Percent of Total
1960-01-01	5.22196326154604
1961-01-01	5.30608292087732
1962-01-01	5.38540976531373
1963-01-01	5.46321788928498
1964-01-01	5.54547618334545
1965-01-01	5.63692132449591
1966-01-01	5.73655140062270
1967-01-01	5.87653391204464
1968-01-01	6.05846934342457
1969-01-01	6.27292257570093
1970-01-01	6.50931180095068
1971-01-01	6.49748303969707
1972-01-01	6.46385022609305
1973-01-01	6.41208640325520
1974-01-01	6.35131430554351
1975-01-01	6.28915994687378
1976-01-01	6.54655608824823
1977-01-01	6.83527697081020
1978-01-01	7.16168893376832
1979-01-01	7.52001869727858
1980-01-01	7.90087810191202
1981-01-01	8.03316545270502
1982-01-01	8.16629976327926
1983-01-01	8.31783511999036
1984-01-01	8.49065224145178
1985-01-01	8.67696893383613
1986-01-01	8.85238910359351
1987-01-01	9.03764145512196
1988-01-01	9.25146931936216
1989-01-01	9.48965046477544
1990-01-01	9.73275819185753
1991-01-01	9.87941447020727
1992-01-01	10.01778704612370
1993-01-01	10.15254895097750
1994-01-01	10.29736327217170
1995-01-01	10.46508318831020
1996-01-01	10.58918233528460
1997-01-01	10.73549011186590
1998-01-01	10.90828729516290
1999-01-01	11.10401880327210
2000-01-01	11.31800376984110
2001-01-01	11.50049198572490
2002-01-01	11.67059357834030
2003-01-01	11.82963550506590
2004-01-01	11.98538062721260
2005-01-01	12.14713234905520
2006-01-01	12.32777815208220
2007-01-01	12.49059477344420
2008-01-01	12.64051921575850
2009-01-01	12.79411302967990
2010-01-01	12.97314575080590
2011-01-01	13.26544705884890
2012-01-01	13.58181684433260
2013-01-01	13.90548978603160
2014-01-01	14.21462949454110
2015-01-01	14.50499329291660
2016-01-01	14.85020187284120
2017-01-01	15.16836280220390