Frequencies for first 10,000 rows of lmpday variable in natl1997 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        595        5.95        5.95
          2 |        259        2.59        8.54
          3 |        258        2.58       11.12
          4 |        232        2.32       13.44
          5 |        373        3.73       17.17
          6 |        246        2.46       19.63
          7 |        210        2.10       21.73
          8 |        239        2.39       24.12
          9 |        191        1.91       26.03
         10 |        393        3.93       29.96
         11 |        190        1.90       31.86
         12 |        256        2.56       34.42
         13 |        220        2.20       36.62
         14 |        222        2.22       38.84
         15 |        657        6.57       45.41
         16 |        231        2.31       47.72
         17 |        252        2.52       50.24
         18 |        216        2.16       52.40
         19 |        196        1.96       54.36
         20 |        410        4.10       58.46
         21 |        246        2.46       60.92
         22 |        227        2.27       63.19
         23 |        256        2.56       65.75
         24 |        245        2.45       68.20
         25 |        358        3.58       71.78
         26 |        209        2.09       73.87
         27 |        205        2.05       75.92
         28 |        300        3.00       78.92
         29 |        194        1.94       80.86
         30 |        222        2.22       83.08
         31 |         70        0.70       83.78
         99 |      1,622       16.22      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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