1901-2000 Degrees Fahrenheit 1 53.7 49.5 4.2 110 20 1895 2018 2011 2001 top-third 1950 2 52.3 48.4 3.9 115 15 1978 1950 2011 1990 top-third 1939,1975 3 52.3 48.4 3.9 116 13 1978 1932 2011 1999 top-tenth 2019 4 53.6 50.1 3.5 119 10 1977 1932 2011 1999 top-tenth 5 55.4 53.1 2.3 110 19 1977 1932 2011 2008 top-third 6 58.6 56.7 1.9 107 22 1977 1932 2011 2008 top-third 7 61.9 59.9 2.0 111 18 1977 1932 2011 2008 top-third 1957 8 64.4 62.4 2.0 117 12 1977 1932 2011 2008 top-tenth 1922,1949 9 66.2 64.0 2.2 121 8 1977 1932,2017 2011 1999 top-tenth 10 66.7 64.7 2.0 121 8 1977 2017 2011 1999 top-tenth 1950 11 66.7 64.6 2.1 121 8 1977 2017 2011 1999 top-tenth 12 66.0 63.9 2.1 123 6 1977 2017 2011 1999 top-tenth 1932 18 62.6 61.5 1.1 106 22 1978 2017 2011 2008 top-third 1975,2007 24 65.2 63.9 1.3 115 13 1978 2017 2011 2008 top-tenth 2008 36 64.6 63.8 0.8 105 22 1970 2018 2011 2009 top-third 1922,1949,1991,1993,1999 48 64.4 63.9 0.5 94 32 1970 2019,2020 2011 2010 top-third 1909,1924,1933,1939,1955,1999,2010 60 64.6 63.9 0.7 111 14 1970 2020 2011 2009 top-third 1923,1953,2002