1901-2000 Inches 1 3.87 2.78 1.09 110 20 1987 1900 1975 1971 top-third 2 8.19 6.08 2.11 118 12 1980 1900 1975 1960 top-tenth 3 13.14 9.58 3.56 122 7 1980 1900 1975 1974 top-tenth 1978 4 17.90 13.50 4.40 115 14 1940 1984 1975 1970 top-third 5 21.71 17.21 4.50 111 18 1948 2006 1975 1970 top-third 6 26.01 20.91 5.10 116 13 1948 2006 1975 1970 top-tenth 7 28.27 24.42 3.85 104 25 1948 2006 1975 1974 top-third 8 32.06 28.20 3.86 97 32 1948 2006 1975 1974 top-third 9 36.29 31.94 4.35 97 32 1948 2006 1975 1974 top-third 10 38.44 35.34 3.10 88 41 2002 2006 1975 1974 top-third 11 41.03 38.65 2.38 84 45 2002 2006 1975 1974 normal 12 44.47 41.99 2.48 87 42 2002 2006 1975 1974 top-third 18 62.68 62.87 -0.19 52 76 2002 2007 1972 1975 normal 24 87.31 83.96 3.35 83 45 1966 2007 1973 1975 normal 36 139.22 125.88 13.34 108 19 1967 2008 1974 1975 top-third 48 188.82 167.88 20.94 115 11 1968 2009 1975 1955 top-tenth 60 225.70 209.81 15.89 103 22 1969 2010 1975 1974 top-third