Frequencies for first 10,000 rows of birwt12 variable in natl1982 dataset :

Birthweight |
  Recode 12 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         12        0.12        0.12
          2 |         42        0.42        0.54
          3 |         57        0.57        1.11
          4 |        126        1.26        2.37
          5 |        448        4.48        6.85
          6 |      1,803       18.03       24.88
          7 |      3,640       36.40       61.28
          8 |      2,786       27.86       89.14
          9 |        864        8.64       97.78
         10 |        182        1.82       99.60
         11 |         30        0.30       99.90
         12 |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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