1925-2000 Degrees Fahrenheit 1 24.4 23.3 1.1 54 46 1985 2016 1977 1980 normal 2 23.2 17.1 6.1 93 7 1972 2019 1980 1965 top-tenth 3 18.4 13.0 5.4 92 8 1972 2019 1980 1981 top-tenth 2003 4 18.9 10.3 8.6 97 3 1971 2016 1980 1981 top-tenth 5 13.6 9.0 4.6 87 12 1971 2016 1980 1942 top-third 6 14.0 9.4 4.6 90 9 1972 2016 1980 1926 top-tenth 7 16.0 11.7 4.3 89 10 1971 2016 1980 1926 top-tenth 8 18.9 15.3 3.6 90 9 1971 2019 1980 1926 top-tenth 9 22.1 19.1 3.0 88 11 1971 2019 1980 1980 top-third 1977,1980 10 25.2 22.5 2.7 87 12 1971 2019 1979 1980 top-third 1977 11 27.3 24.9 2.4 86 13 1971 2019 1979 1980 top-third 1958,2020 12 28.3 26.0 2.3 84 15 1971 2016 1979 1980 top-third 1941,1958,2021 18 22.9 20.4 2.5 84 14 1972 2016 1980 1978 top-third 1945,1978,1988,1998,2006 24 28.4 26.0 2.4 87 11 1972 2019 1980 1981 top-third 2021 36 28.0 26.0 2.0 83 14 1973 2016 1980 1981 top-third 48 27.9 25.9 2.0 81 15 1974 2019 1980 1980 top-third 1980 60 27.9 25.9 2.0 81 14 1975 2019 1980 1981 top-third