Year	Number of Years
1960-01-01	52.5716582758048
1961-01-01	53.0774728325625
1962-01-01	53.5015977154438
1963-01-01	54.0355302062577
1964-01-01	54.7152220840023
1965-01-01	55.3845267792003
1966-01-01	56.1254252444584
1967-01-01	56.8396020348807
1968-01-01	57.4460565357179
1969-01-01	58.0603092467296
1970-01-01	58.6533482244209
1971-01-01	59.1799367063007
1972-01-01	59.6653374383996
1973-01-01	60.1122364806538
1974-01-01	60.6047003268051
1975-01-01	61.0464445280570
1976-01-01	61.4626255552456
1977-01-01	61.8798775897337
1978-01-01	62.2334605403321
1979-01-01	62.5879420132019
1980-01-01	62.8665870553188
1981-01-01	63.1996694054485
1982-01-01	63.5172326600558
1983-01-01	63.7575261423087
1984-01-01	64.0158557206774
1985-01-01	64.2667536020301
1986-01-01	64.5641490583736
1987-01-01	64.8156513445867
1988-01-01	65.0220931009529
1989-01-01	65.2409179077772
1990-01-01	65.4351535994166
1991-01-01	65.6238191640542
1992-01-01	65.7886194296555
1993-01-01	65.9151822189660
1994-01-01	66.1252280244934
1995-01-01	66.3231792265744
1996-01-01	66.6127919913952
1997-01-01	66.9115240376161
1998-01-01	67.1724780323923
1999-01-01	67.4057220559480
2000-01-01	67.6849977963724
2001-01-01	67.9836154055130
2002-01-01	68.2499165643793
2003-01-01	68.5243016783886
2004-01-01	68.8633377948824
2005-01-01	69.1362132966640
2006-01-01	69.4749754246644
2007-01-01	69.7943051807231
2008-01-01	70.0834595932328
2009-01-01	70.4056046446669
2010-01-01	70.6829258238569
2011-01-01	70.9718158692994
2012-01-01	71.2153439902819
2013-01-01	71.4601348728572
2014-01-01	71.6941340330603
2015-01-01	71.8571267618128
2016-01-01	72.0353369349926