Year	Number of Years
1960-01-01	41.9539025639737
1961-01-01	42.5936571252509
1962-01-01	43.2365527869596
1963-01-01	43.8833834173156
1964-01-01	44.5318721108674
1965-01-01	45.1745457244460
1966-01-01	45.8028439831529
1967-01-01	46.4099766122955
1968-01-01	46.9931743138624
1969-01-01	47.5556345728019
1970-01-01	48.1096261476058
1971-01-01	48.6718013818554
1972-01-01	49.2549245824011
1973-01-01	49.8647424295837
1974-01-01	50.4961990141961
1975-01-01	51.1394610379148
1976-01-01	51.7779706012972
1977-01-01	52.3955497152669
1978-01-01	52.9785061950392
1979-01-01	53.5211920680223
1980-01-01	54.0189647719809
1981-01-01	54.4720210734968
1982-01-01	54.8903318374756
1983-01-01	55.2865614936639
1984-01-01	55.6696332457308
1985-01-01	56.0499834803622
1986-01-01	56.4407617578084
1987-01-01	56.8468942159691
1988-01-01	57.2736353176451
1989-01-01	57.7219632477894
1990-01-01	58.1914866615810
1991-01-01	58.6786066984053
1992-01-01	59.1742276673268
1993-01-01	59.6694331833226
1994-01-01	60.1604122239743
1995-01-01	60.6425788538661
1996-01-01	61.1128485125584
1997-01-01	61.5700881373410
1998-01-01	62.0155923176471
1999-01-01	62.4476908971906
2000-01-01	62.8652218301737
2001-01-01	63.2716067015990
2002-01-01	63.6694470171634
2003-01-01	64.0614329425638
2004-01-01	64.4513170221394
2005-01-01	64.8423033366327
2006-01-01	65.2371142333509
2007-01-01	65.6364625231213
2008-01-01	66.0371485828198
2009-01-01	66.4365292656335
2010-01-01	66.8267569031017
2011-01-01	67.2011962411029
2012-01-01	67.5537216461953
2013-01-01	67.8811450205299
2014-01-01	68.1810815941811
2015-01-01	68.4565258804813
2016-01-01	68.7105330531220