Year	Number of Years
1960-01-01	38.418
1961-01-01	39.074
1962-01-01	39.693
1963-01-01	40.259
1964-01-01	40.768
1965-01-01	41.222
1966-01-01	41.631
1967-01-01	42.016
1968-01-01	42.395
1969-01-01	42.774
1970-01-01	43.157
1971-01-01	43.547
1972-01-01	43.935
1973-01-01	44.317
1974-01-01	44.691
1975-01-01	45.055
1976-01-01	45.405
1977-01-01	45.740
1978-01-01	46.059
1979-01-01	46.364
1980-01-01	46.654
1981-01-01	46.927
1982-01-01	47.187
1983-01-01	47.441
1984-01-01	47.695
1985-01-01	47.956
1986-01-01	48.230
1987-01-01	48.523
1988-01-01	48.841
1989-01-01	49.193
1990-01-01	49.589
1991-01-01	50.040
1992-01-01	50.545
1993-01-01	51.099
1994-01-01	51.693
1995-01-01	52.311
1996-01-01	52.932
1997-01-01	53.539
1998-01-01	54.126
1999-01-01	54.693
2000-01-01	55.258
2001-01-01	55.847
2002-01-01	56.483
2003-01-01	57.174
2004-01-01	57.916
2005-01-01	58.691
2006-01-01	59.472
2007-01-01	60.230
2008-01-01	60.940
2009-01-01	61.591
2010-01-01	62.181
2011-01-01	62.718
2012-01-01	63.220
2013-01-01	63.703
2014-01-01	64.174
2015-01-01	64.636
2016-01-01	65.092