Frequencies for first 10,000 rows of birwt3 variable in natl1971 dataset :

Birthweight |
   Recode 3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        802        8.02        8.02
          2 |      9,174       91.74       99.76
          3 |         24        0.24      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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