Frequencies for first 10,000 rows of usetobac variable in namcs2001 dataset :

       does |
patient use |
   tobacco? |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        468        4.68        4.68
          1 |        816        8.16       12.84
          2 |      5,482       54.82       67.66
          3 |      3,234       32.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016