Frequencies for first 10,000 rows of lmpmon variable in natl1992 dataset :

 Month Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         20        0.20        0.20
          2 |         74        0.74        0.94
          3 |        979        9.79       10.73
          4 |      3,642       36.42       47.15
          5 |      3,651       36.51       83.66
          6 |      1,114       11.14       94.80
          7 |        174        1.74       96.54
          8 |         62        0.62       97.16
          9 |         28        0.28       97.44
         10 |         10        0.10       97.54
         11 |          7        0.07       97.61
         12 |          9        0.09       97.70
         99 |        230        2.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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