Frequencies for first 10,000 rows of tobacco variable in natl1994 dataset :

Tobacco Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,349       13.49       13.49
          2 |      8,620       86.20       99.69
          9 |         31        0.31      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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