Year	Number of Years
1960-01-01	43.204
1961-01-01	43.511
1962-01-01	43.817
1963-01-01	44.121
1964-01-01	44.424
1965-01-01	44.728
1966-01-01	45.033
1967-01-01	45.340
1968-01-01	45.650
1969-01-01	45.962
1970-01-01	46.273
1971-01-01	46.578
1972-01-01	46.876
1973-01-01	47.166
1974-01-01	47.449
1975-01-01	47.722
1976-01-01	47.985
1977-01-01	48.244
1978-01-01	48.503
1979-01-01	48.771
1980-01-01	49.060
1981-01-01	49.380
1982-01-01	49.740
1983-01-01	50.140
1984-01-01	50.580
1985-01-01	51.055
1986-01-01	51.553
1987-01-01	52.064
1988-01-01	52.576
1989-01-01	53.085
1990-01-01	53.589
1991-01-01	54.090
1992-01-01	54.594
1993-01-01	55.106
1994-01-01	55.628
1995-01-01	56.158
1996-01-01	56.698
1997-01-01	57.246
1998-01-01	57.801
1999-01-01	58.359
2000-01-01	58.923
2001-01-01	59.494
2002-01-01	60.070
2003-01-01	60.648
2004-01-01	61.224
2005-01-01	61.793
2006-01-01	62.348
2007-01-01	62.886
2008-01-01	63.402
2009-01-01	63.893
2010-01-01	64.357
2011-01-01	64.795
2012-01-01	65.208
2013-01-01	65.600
2014-01-01	65.975
2015-01-01	66.335
2016-01-01	66.683