Frequencies for first 10,000 rows of lmpmon variable in natlterr1995 dataset :

 Month Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |          1        0.01        0.01
          3 |        672        6.72        6.73
          4 |      4,240       42.40       49.13
          5 |      4,054       40.54       89.67
          6 |        711        7.11       96.78
          7 |        110        1.10       97.88
          8 |         32        0.32       98.20
          9 |          5        0.05       98.25
         99 |        175        1.75      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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