Frequencies for first 10,000 rows of lmpday variable in natl1979 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        519        5.19        5.19
          2 |        216        2.16        7.35
          3 |        233        2.33        9.68
          4 |        209        2.09       11.77
          5 |        323        3.23       15.00
          6 |        221        2.21       17.21
          7 |        237        2.37       19.58
          8 |        247        2.47       22.05
          9 |        209        2.09       24.14
         10 |        417        4.17       28.31
         11 |        198        1.98       30.29
         12 |        242        2.42       32.71
         13 |        213        2.13       34.84
         14 |        232        2.32       37.16
         15 |        670        6.70       43.86
         16 |        234        2.34       46.20
         17 |        220        2.20       48.40
         18 |        259        2.59       50.99
         19 |        203        2.03       53.02
         20 |        411        4.11       57.13
         21 |        203        2.03       59.16
         22 |        205        2.05       61.21
         23 |        215        2.15       63.36
         24 |        234        2.34       65.70
         25 |        357        3.57       69.27
         26 |        242        2.42       71.69
         27 |        220        2.20       73.89
         28 |        291        2.91       76.80
         29 |        170        1.70       78.50
         30 |        186        1.86       80.36
         31 |         79        0.79       81.15
         99 |      1,885       18.85      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016