Frequencies for first 10,000 rows of alcohol variable in natl1993 dataset :

Alcohol Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        159        1.59        1.59
          2 |      9,823       98.23       99.82
          9 |         18        0.18      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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