Frequencies for first 10,000 rows of dtotord variable in natl1978 dataset :

Total birth |
      order |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      3,860       38.60       38.60
          2 |      3,027       30.27       68.87
          3 |      1,641       16.41       85.28
          4 |        743        7.43       92.71
          5 |        322        3.22       95.93
          6 |        156        1.56       97.49
          7 |         94        0.94       98.43
          8 |         52        0.52       98.95
          9 |         40        0.40       99.35
         10 |         24        0.24       99.59
         11 |         17        0.17       99.76
         12 |          6        0.06       99.82
         13 |          6        0.06       99.88
         14 |          3        0.03       99.91
         15 |          1        0.01       99.92
         16 |          1        0.01       99.93
         17 |          3        0.03       99.96
         18 |          1        0.01       99.97
         99 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016