1925-2000 Degrees Fahrenheit 1 28.1 25.5 2.6 67 32 1996 2013 1939 1938 top-third 1949 2 34.7 33.0 1.7 65 34 1992 2018 1939 1938 normal 3 39.9 38.5 1.4 65 34 1996 2018 1939 1938 normal 1934,1993,2015 4 43.3 42.1 1.2 68 31 1970 2019 1939 1938 top-third 5 44.7 43.5 1.2 70 29 1970 2019 1939 1938 top-third 2010 6 44.1 42.6 1.5 74 25 1965,1970 2019 1939 1936 top-third 2003,2010 7 42.5 39.8 2.7 88 11 1985 2016,2019 1939 1926 top-third 2007,2020 8 38.7 36.2 2.5 87 12 1971 2019 1939 1926 top-third 2020,2022 9 35.4 32.7 2.7 88 11 1971 2019 1939 1926 top-third 1942 10 32.8 29.6 3.2 87 12 1971 2016 1939 1926 top-third 11 30.6 27.3 3.3 90 8 1971 2016 1939 1926 top-tenth 2014 12 28.4 26.0 2.4 83 15 1956 2016 1939 1926 top-third 1981,1987 18 32.7 31.5 1.2 68 30 1956,1971 2016,2019 1939 1926 top-third 1978,1988,1993 24 27.1 25.9 1.2 67 30 1972 2019 1939 1927 top-third 2010 36 26.9 25.9 1.0 66 30 1973 2016 1939 1940 top-third 1987,2014 48 26.8 25.9 0.9 58 37 1974 2019 1939 1929 normal 1983,2000,2010 60 26.7 25.9 0.8 54 40 1975 2019 1939 1930 normal 1930,1984