Frequencies for first 10,000 rows of tobacco variable in natl1992 dataset :

Tobacco Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,518       15.18       15.18
          2 |      8,476       84.76       99.94
          9 |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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