Frequencies for first 10,000 rows of tobacco variable in natlterr2001 dataset :

Tobacco Use |
     During |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        100        1.00        1.00
          2 |      9,879       98.79       99.79
          9 |         21        0.21      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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