Frequencies for first 10,000 rows of usetobac variable in namcs2014 dataset :

Tobacco Use |      Freq.     Percent        Cum.
------------+-----------------------------------
      Blank |        226        2.26        2.26
    Unknown |      2,012       20.12       22.38
      Never |      5,467       54.67       77.05
     Former |      1,446       14.46       91.51
    Current |        849        8.49      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017