Year	Number of Years
1960-01-01	70.3487804878049
1961-01-01	70.5126829268293
1962-01-01	69.7868292682927
1963-01-01	70.3043902439025
1964-01-01	70.4595121951220
1965-01-01	70.1631707317073
1966-01-01	70.3848780487805
1967-01-01	70.2641463414634
1968-01-01	69.8407317073171
1969-01-01	69.3670731707317
1970-01-01	69.4402439024390
1971-01-01	69.6770731707317
1972-01-01	70.1765853658537
1973-01-01	70.0226829268293
1974-01-01	70.0865853658537
1975-01-01	70.4146341463415
1976-01-01	70.5326829268293
1977-01-01	70.5734146341463
1978-01-01	70.6439024390244
1979-01-01	70.7495121951220
1980-01-01	70.2780487804878
1981-01-01	70.7221951219512
1982-01-01	70.8078048780488
1983-01-01	70.5914634146341
1984-01-01	70.8375609756098
1985-01-01	71.0463414634146
1986-01-01	70.9973170731707
1987-01-01	71.4456097560976
1988-01-01	71.6414634146342
1989-01-01	71.6756097560976
1990-01-01	71.3839024390244
1991-01-01	71.8982926829268
1992-01-01	72.2717073170732
1993-01-01	72.7678048780488
1994-01-01	72.9726829268293
1995-01-01	73.0748780487805
1996-01-01	73.7146341463415
1997-01-01	73.8248780487805
1998-01-01	74.5146341463415
1999-01-01	74.6682926829268
2000-01-01	74.9682926829268
2001-01-01	75.1731707317073
2002-01-01	75.2219512195122
2003-01-01	75.1707317073171
2004-01-01	75.7219512195122
2005-01-01	75.9243902439025
2006-01-01	76.5243902439024
2007-01-01	76.7243902439025
2008-01-01	76.9756097560976
2009-01-01	77.0780487804878
2010-01-01	77.4243902439025
2011-01-01	77.8731707317073
2012-01-01	78.0756097560976
2013-01-01	78.1756097560976
2014-01-01	78.8243902439024
2015-01-01	78.5780487804878
2016-01-01	78.3317073170732