Frequencies for first 10,000 rows of alcohol variable in natl1999 dataset :

Alcohol Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         58        0.58        0.58
          2 |      9,936       99.36       99.94
          9 |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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