Year,Value,Contiguous U.S. (Lower 48),Temp,Jan-Jul,(°F)
1940,48.365
1941,49.222
1942,48.84
1943,50.291
1944,50.307
1945,50.003
1946,51.328
1947,48.581
1948,50.399
1949,50.96
1950,50.41
1951,50.808
1952,52.06
1953,52.785
1954,52.76
1955,50.981
1956,51.432
1957,51.584
1958,50.949
1959,51.605
1960,50.473
1961,51.724
1962,50.711
1963,51.25
1964,51.329
1965,50.404
1966,50.785
1967,51.35
1968,51.045
1969,50.742
1970,50.954
1971,50.762
1972,51.627
1973,51.419
1974,52.494
1975,50.644
1976,52.244
1977,52.282
1978,50.226
1979,49.417
1980,51.88
1981,53.241
1982,50.379
1983,51.596
1984,51.547
1985,51.701
1986,53.817
1987,53.341
1988,52.29
1989,52.09
1990,53.671
1991,53.227
1992,53.218
1993,50.885
1994,52.499
1995,52.231
1996,51.567
1997,51.388
1998,53.096
1999,52.973
2000,54.176
2001,52.38
2002,53.055
2003,52.385
2004,52.678
2005,53.29
2006,55.047
2007,53.308
2008,52.143
2009,52.587
2010,52.569
2011,52.428
2012,56.417
2013,52.529
2014,51.837
2015,53.598
2016,54.964
2017,55.229
2018,53.978
2019,52.259
2020,54.525
2021,53.812
2022,53.508
2023,53.771
2024,54.933
2025,53.968