Frequencies for first 10,000 rows of birwt12 variable in natl1999 dataset :

Birthweight |
  Recode 12 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         23        0.23        0.23
          2 |         64        0.64        0.87
          3 |         99        0.99        1.86
          4 |        178        1.78        3.64
          5 |        536        5.36        9.00
          6 |      1,864       18.64       27.64
          7 |      3,732       37.32       64.96
          8 |      2,644       26.44       91.40
          9 |        720        7.20       98.60
         10 |        127        1.27       99.87
         11 |          8        0.08       99.95
         12 |          5        0.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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