Frequencies for first 10,000 rows of birwt4 variable in natl1991 dataset :

Birthweight |
   Recode 4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        122        1.22        1.22
          2 |        617        6.17        7.39
          3 |      9,258       92.58       99.97
          4 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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