Frequencies for first 10,000 rows of cig_0 variable in natl2017 dataset :

 Cigarettes |
     Before |
  Pregnancy |
      00-97 |
  Number of |
 cigarettes |
      daily |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,458       84.58       84.58
          1 |         24        0.24       84.82
          2 |         72        0.72       85.54
          3 |         83        0.83       86.37
          4 |         76        0.76       87.13
          5 |        180        1.80       88.93
          6 |         78        0.78       89.71
          7 |         31        0.31       90.02
          8 |         38        0.38       90.40
          9 |          8        0.08       90.48
         10 |        257        2.57       93.05
         11 |          1        0.01       93.06
         12 |         14        0.14       93.20
         13 |          2        0.02       93.22
         14 |          2        0.02       93.24
         15 |         47        0.47       93.71
         16 |          2        0.02       93.73
         18 |          3        0.03       93.76
         20 |        280        2.80       96.56
         22 |          1        0.01       96.57
         23 |          2        0.02       96.59
         24 |          9        0.09       96.68
         25 |          8        0.08       96.76
         26 |          4        0.04       96.80
         27 |          2        0.02       96.82
         28 |          2        0.02       96.84
         30 |         24        0.24       97.08
         32 |          4        0.04       97.12
         33 |          1        0.01       97.13
         35 |          1        0.01       97.14
         37 |          1        0.01       97.15
         40 |         33        0.33       97.48
         60 |          6        0.06       97.54
         65 |          1        0.01       97.55
         80 |         20        0.20       97.75
         84 |          1        0.01       97.76
         89 |          1        0.01       97.77
         90 |          1        0.01       97.78
         98 |          1        0.01       97.79
         99 |        221        2.21      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 19 Sep 2018