Frequencies for first 10,000 rows of alcohol variable in natl1990 dataset :

Alcohol Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        187        1.87        1.87
          2 |      9,743       97.43       99.30
          9 |         70        0.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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