Frequencies for first 10,000 rows of lmpmon variable in natl1991 dataset :

 Month Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         19        0.19        0.19
          2 |         72        0.72        0.91
          3 |      1,056       10.56       11.47
          4 |      3,398       33.98       45.45
          5 |      3,412       34.12       79.57
          6 |      1,422       14.22       93.79
          7 |        251        2.51       96.30
          8 |         67        0.67       96.97
          9 |         29        0.29       97.26
         10 |          8        0.08       97.34
         11 |          8        0.08       97.42
         12 |          9        0.09       97.51
         99 |        249        2.49      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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