Year	Number of Years
1960-01-01	54.6009231598976
1961-01-01	55.1511806901478
1962-01-01	55.6822258375895
1963-01-01	56.1932581470476
1964-01-01	56.6845516557508
1965-01-01	57.1601980039440
1966-01-01	57.6255379474971
1967-01-01	58.0849847984207
1968-01-01	58.5429463531806
1969-01-01	58.9997962338844
1970-01-01	59.4532454983032
1971-01-01	59.9004681571035
1972-01-01	60.3355223490861
1973-01-01	60.7558710896726
1974-01-01	61.1613626620259
1975-01-01	61.5535240641398
1976-01-01	61.9365383805121
1977-01-01	62.3149054880761
1978-01-01	62.6926797175959
1979-01-01	63.0719435243535
1980-01-01	63.4527296810758
1981-01-01	63.8338716064599
1982-01-01	64.2140872941676
1983-01-01	64.5873019270077
1984-01-01	64.9586867912728
1985-01-01	65.3256880969270
1986-01-01	65.6883317907646
1987-01-01	66.0481359409574
1988-01-01	66.4048071175458
1989-01-01	66.7629242592258
1990-01-01	67.1272015397684
1991-01-01	67.5030274067513
1992-01-01	67.8932496855926
1993-01-01	68.2942304399440
1994-01-01	68.7068912237003
1995-01-01	69.1250271356365
1996-01-01	69.5425786639500
1997-01-01	69.9534030406440
1998-01-01	70.3487203359703
1999-01-01	70.7267405679957
2000-01-01	71.0840676462609
2001-01-01	71.4197534293778
2002-01-01	71.7376942139260
2003-01-01	72.0396247757775
2004-01-01	72.3296282205290
2005-01-01	72.6096942203558
2006-01-01	72.8822031414918
2007-01-01	73.1490195727958
2008-01-01	73.4108657304912
2009-01-01	73.6692339651193
2010-01-01	73.9224147133129
2011-01-01	74.1701151987694
2012-01-01	74.4097324494745
2013-01-01	74.6403948358198
2014-01-01	74.8628564002532
2015-01-01	75.0776424083584
2016-01-01	75.2866736438754