Frequencies for first 10,000 rows of birwt4 variable in natl1992 dataset :

Birthweight |
   Recode 4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        146        1.46        1.46
          2 |        662        6.62        8.08
          3 |      9,187       91.87       99.95
          4 |          5        0.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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