Year	Number of Years
1960-01-01	62.8089268292683
1961-01-01	63.2523658536585
1962-01-01	63.6941463414634
1963-01-01	64.1322926829268
1964-01-01	64.5638536585366
1965-01-01	64.9894634146342
1966-01-01	65.4062682926829
1967-01-01	65.8168292682927
1968-01-01	66.2216585365854
1969-01-01	66.6217560975610
1970-01-01	67.0731707317073
1971-01-01	66.7707317073171
1972-01-01	68.3243902439024
1973-01-01	67.5243902439024
1974-01-01	68.0195121951220
1975-01-01	68.3097560975610
1976-01-01	68.8609756097561
1977-01-01	70.0121951219512
1978-01-01	70.3170731707317
1979-01-01	71.1682926829268
1980-01-01	71.2146341463415
1981-01-01	71.6146341463415
1982-01-01	72.4146341463415
1983-01-01	72.2658536585366
1984-01-01	72.5146341463415
1985-01-01	72.8146341463415
1986-01-01	73.2658536585366
1987-01-01	73.6658536585366
1988-01-01	73.7146341463415
1989-01-01	74.2658536585366
1990-01-01	73.9658536585366
1991-01-01	74.0146341463415
1992-01-01	74.3121951219512
1993-01-01	74.5121951219512
1994-01-01	74.9146341463415
1995-01-01	75.3121951219512
1996-01-01	75.2609756097561
1997-01-01	75.4121951219512
1998-01-01	75.7121951219512
1999-01-01	75.9634146341463
2000-01-01	76.3146341463415
2001-01-01	76.8146341463415
2002-01-01	77.0658536585366
2003-01-01	77.2195121951220
2004-01-01	77.6707317073171
2005-01-01	78.0707317073171
2006-01-01	78.4195121951220
2007-01-01	78.3219512195122
2008-01-01	78.5243902439025
2009-01-01	78.7268292682927
2010-01-01	79.0268292682927
2011-01-01	80.4707317073171
2012-01-01	80.3731707317073
2013-01-01	80.7219512195122
2014-01-01	81.1219512195122
2015-01-01	81.1243902439025
2016-01-01	81.1268292682927