1925-2000 Degrees Fahrenheit 1 33.8 37.8 -4.0 5 94 1964 2015 1945 1948 bottom-tenth 1945 2 25.4 30.6 -5.2 2 97 1985 2016 1949 1948 bottom-tenth 1964 3 23.2 24.0 -0.8 34 65 1972 2019 1948 1947 normal 1944 4 16.9 19.2 -2.3 18 81 1972 2019 1946 1948 bottom-third 5 14.1 15.8 -1.7 23 76 1971 2016 1947 1948 bottom-third 1947 6 11.1 13.8 -2.7 11 87 1971 2016 1947 1948 bottom-third 1943 7 10.2 13.5 -3.3 7 91 1972 2016 1949 1948 bottom-tenth 8 12.0 15.0 -3.0 7 91 1971 2016 1949 1948 bottom-tenth 1964 9 14.8 17.8 -3.0 5 93 1971 2019 1949 1948 bottom-tenth 10 17.9 21.0 -3.1 4 94 1971 2019 1949 1948 bottom-tenth 1976 11 20.9 23.9 -3.0 4 94 1971 2019 1949 1948 bottom-tenth 12 23.2 26.0 -2.8 4 94 1971 2016,2019 1949 1948 bottom-tenth 1976 18 20.1 21.9 -1.8 11 86 1972 2016,2019 1934 1948 bottom-third 1974 24 24.6 26.0 -1.4 13 84 1972 2019 1947 1948 bottom-third 1950,1967 36 24.5 26.0 -1.5 9 87 1973 2016 1934 1948 bottom-tenth 1975 48 24.5 25.9 -1.4 7 88 1974 2019 1949 1948 bottom-tenth 1967 60 25.1 25.9 -0.8 17 77 1975 2019 1936 1948 bottom-third 1934,1958