Frequencies for first 10,000 rows of lmpmon variable in natlterr1996 dataset :

 Month Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          3 |        633        6.33        6.33
          4 |      4,165       41.65       47.98
          5 |      4,219       42.19       90.17
          6 |        717        7.17       97.34
          7 |         89        0.89       98.23
          8 |         26        0.26       98.49
          9 |          4        0.04       98.53
         10 |          1        0.01       98.54
         99 |        146        1.46      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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