Frequencies for first 10,000 rows of birwt12 variable in natlterr1999 dataset :

Birthweight |
  Recode 12 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         10        0.10        0.10
          2 |         48        0.48        0.58
          3 |         64        0.64        1.22
          4 |        177        1.77        2.99
          5 |        758        7.58       10.57
          6 |      2,760       27.60       38.17
          7 |      4,036       40.36       78.53
          8 |      1,814       18.14       96.67
          9 |        293        2.93       99.60
         10 |         31        0.31       99.91
         11 |          4        0.04       99.95
         12 |          5        0.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015