Annual Number of Years
1960-01-01 48.4552640139166
1961-01-01 48.9884654158502
1962-01-01 49.6622455253740
1963-01-01 50.6413404510660
1964-01-01 51.8425436268996
1965-01-01 53.2155625097082
1966-01-01 54.7521461201069
1967-01-01 56.2427580998421
1968-01-01 57.6179022580812
1969-01-01 58.8570576027628
1970-01-01 59.9089070965427
1971-01-01 60.8283542094542
1972-01-01 61.6220098919438
1973-01-01 62.3191791621831
1974-01-01 63.0197288275235
1975-01-01 63.6908571728180
1976-01-01 64.3011023258151
1977-01-01 64.8842963825098
1978-01-01 65.4068036289471
1979-01-01 65.8975012640274
1980-01-01 66.3095315386110
1981-01-01 66.7239149994520
1982-01-01 67.1126717494892
1983-01-01 67.4281612698751
1984-01-01 67.7553971939424
1985-01-01 68.0414387466691
1986-01-01 68.3121182724063
1987-01-01 68.5578757360958
1988-01-01 68.7446944991245
1989-01-01 68.9543661821556
1990-01-01 69.1299358123777
1991-01-01 69.3161176451294
1992-01-01 69.4752973116647
1993-01-01 69.6508452446988
1994-01-01 69.8496122110574
1995-01-01 70.0275429856225
1996-01-01 70.3037064750155
1997-01-01 70.5849645434091
1998-01-01 70.8815161721325
1999-01-01 71.2018842162962
2000-01-01 71.5790095318242
2001-01-01 71.9521541854592
2002-01-01 72.3032306985278
2003-01-01 72.6413387994024
2004-01-01 72.9632426457228
2005-01-01 73.2337762134081
2006-01-01 73.5158126814504
2007-01-01 73.7610119967372
2008-01-01 73.9808397352339
2009-01-01 74.2072639953092
2010-01-01 74.3839146463837
2011-01-01 74.5460644618497
2012-01-01 74.7411842008234
2013-01-01 74.9190715423245
2014-01-01 75.0860081183076
2015-01-01 75.2489157797135
2016-01-01 75.3957316449765