Year	Number of Years
1960-01-01	69.7019512195122
1961-01-01	70.5209756097561
1962-01-01	70.2195121951220
1963-01-01	70.0514634146342
1964-01-01	70.7551219512195
1965-01-01	70.6253658536586
1966-01-01	70.7063414634146
1967-01-01	71.0129268292683
1968-01-01	70.6931707317073
1969-01-01	70.7648780487805
1970-01-01	70.9719512195122
1971-01-01	71.0604878048781
1972-01-01	71.4051219512195
1973-01-01	71.6353658536586
1974-01-01	71.9858536585366
1975-01-01	71.9712195121951
1976-01-01	72.1197560975610
1977-01-01	72.7739024390244
1978-01-01	72.6980487804878
1979-01-01	73.1936585365854
1980-01-01	73.2070731707317
1981-01-01	73.6217073170732
1982-01-01	73.8880487804878
1983-01-01	73.8690243902439
1984-01-01	74.4048780487805
1985-01-01	74.5202439024390
1986-01-01	74.7317073170732
1987-01-01	75.3658536585366
1988-01-01	75.5658536585366
1989-01-01	75.6326829268293
1990-01-01	76.0519512195122
1991-01-01	76.1921951219512
1992-01-01	76.3512195121951
1993-01-01	76.3453658536585
1994-01-01	76.6917073170732
1995-01-01	76.8407317073171
1996-01-01	77.1873170731707
1997-01-01	77.3707317073171
1998-01-01	77.4731707317073
1999-01-01	77.6195121951220
2000-01-01	77.7219512195122
2001-01-01	77.9731707317073
2002-01-01	78.0756097560976
2003-01-01	78.1292682926829
2004-01-01	78.8780487804878
2005-01-01	78.9804878048781
2006-01-01	79.3804878048780
2007-01-01	79.7829268292683
2008-01-01	79.6804878048781
2009-01-01	80.0341463414634
2010-01-01	80.1829268292683
2011-01-01	80.5853658536585
2012-01-01	80.3853658536585
2013-01-01	80.5878048780488
2014-01-01	81.2878048780488
2015-01-01	80.9926829268293
2016-01-01	80.9926829268293