Frequencies for first 10,000 rows of cig_1 variable in natlterr2005 dataset :

 Cigarettes |
        1st |
  Trimester |
        RFP |
575=f_tobac |
        o R |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      3,722       37.22       37.22
          1 |          3        0.03       37.25
          2 |          5        0.05       37.30
          3 |          1        0.01       37.31
          5 |          1        0.01       37.32
          6 |          1        0.01       37.33
          7 |          1        0.01       37.34
          8 |          1        0.01       37.35
         10 |          4        0.04       37.39
         20 |          5        0.05       37.44
         40 |          1        0.01       37.45
          . |      6,255       62.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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