Year	Number of Years
1960-01-01	70.8170731707317
1961-01-01	70.9731707317073
1962-01-01	70.9424390243903
1963-01-01	70.9117073170732
1964-01-01	70.8809756097561
1965-01-01	70.8502439024390
1966-01-01	70.8195121951220
1967-01-01	70.8692682926829
1968-01-01	70.9190243902439
1969-01-01	70.9687804878049
1970-01-01	71.0185365853659
1971-01-01	71.0682926829268
1972-01-01	71.4575609756098
1973-01-01	71.8468292682927
1974-01-01	72.2360975609756
1975-01-01	72.6253658536586
1976-01-01	73.0146341463415
1977-01-01	73.3443902439024
1978-01-01	73.6741463414634
1979-01-01	74.0039024390244
1980-01-01	74.3336585365854
1981-01-01	74.6634146341463
1982-01-01	74.9048780487805
1983-01-01	75.1463414634146
1984-01-01	75.3878048780488
1985-01-01	75.6292682926829
1986-01-01	75.8707317073171
1987-01-01	76.1517073170732
1988-01-01	76.4326829268293
1989-01-01	76.7136585365854
1990-01-01	76.9946341463415
1991-01-01	77.2756097560976
1992-01-01	77.3780487804878
1993-01-01	77.8780487804878
1994-01-01	77.8780487804878
1995-01-01	77.8292682926829
1996-01-01	78.0780487804878
1997-01-01	78.4804878048781
1998-01-01	78.6317073170732
1999-01-01	78.9317073170732
2000-01-01	79.2341463414634
2001-01-01	79.6341463414634
2002-01-01	79.9365853658537
2003-01-01	80.2390243902439
2004-01-01	80.4902439024390
2005-01-01	80.8414634146341
2006-01-01	81.0414634146342
2007-01-01	81.2926829268293
2008-01-01	81.3951219512195
2009-01-01	81.5439024390244
2010-01-01	81.6951219512195
2011-01-01	81.8951219512195
2012-01-01	82.0463414634146
2013-01-01	82.1487804878049
2014-01-01	82.3000000000000
2015-01-01	82.4000000000000
2016-01-01	82.5000000000000