Annual Number of Years
1960-01-01 47.7014789341713
1961-01-01 48.2411839510604
1962-01-01 48.8654739755208
1963-01-01 49.6034956981523
1964-01-01 50.4644562331008
1965-01-01 51.4124168704456
1966-01-01 52.3966506526263
1967-01-01 53.3660886072347
1968-01-01 54.2781966434566
1969-01-01 55.1008514454760
1970-01-01 55.8525991012485
1971-01-01 56.5208958091549
1972-01-01 57.1214162308990
1973-01-01 57.7073759926043
1974-01-01 58.2749367204531
1975-01-01 58.7914502413568
1976-01-01 59.3042823129460
1977-01-01 59.7883815086756
1978-01-01 60.2430181891404
1979-01-01 60.6473983913155
1980-01-01 61.0339568902598
1981-01-01 61.3998806447203
1982-01-01 61.7534745123245
1983-01-01 62.0661051669086
1984-01-01 62.3534713275572
1985-01-01 62.6764965881524
1986-01-01 63.0314225427351
1987-01-01 63.3222483556667
1988-01-01 63.5978419859614
1989-01-01 63.8571328679037
1990-01-01 64.1067505621127
1991-01-01 64.3469464737231
1992-01-01 64.5326748241884
1993-01-01 64.7048407643032
1994-01-01 64.9376509670097
1995-01-01 65.2027583803683
1996-01-01 65.5152227315201
1997-01-01 65.8468805369683
1998-01-01 66.1557317387349
1999-01-01 66.4314062147713
2000-01-01 66.7315273831411
2001-01-01 67.0428843979510
2002-01-01 67.3425174913558
2003-01-01 67.6495205806687
2004-01-01 67.9698538130934
2005-01-01 68.2714442396306
2006-01-01 68.6092081725337
2007-01-01 68.9348713605665
2008-01-01 69.2400305993889
2009-01-01 69.5642625130008
2010-01-01 69.8557975594871
2011-01-01 70.1560017377865
2012-01-01 70.4235363940129
2013-01-01 70.6809432855081
2014-01-01 70.9084091299172
2015-01-01 71.1266833653779
2016-01-01 71.3337250409241