Frequencies for first 10,000 rows of lmpday variable in natl1988 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        513        5.13        5.13
          2 |        209        2.09        7.22
          3 |        256        2.56        9.78
          4 |        248        2.48       12.26
          5 |        336        3.36       15.62
          6 |        237        2.37       17.99
          7 |        238        2.38       20.37
          8 |        260        2.60       22.97
          9 |        186        1.86       24.83
         10 |        374        3.74       28.57
         11 |        193        1.93       30.50
         12 |        221        2.21       32.71
         13 |        222        2.22       34.93
         14 |        221        2.21       37.14
         15 |        710        7.10       44.24
         16 |        210        2.10       46.34
         17 |        229        2.29       48.63
         18 |        231        2.31       50.94
         19 |        201        2.01       52.95
         20 |        385        3.85       56.80
         21 |        236        2.36       59.16
         22 |        208        2.08       61.24
         23 |        237        2.37       63.61
         24 |        217        2.17       65.78
         25 |        368        3.68       69.46
         26 |        220        2.20       71.66
         27 |        255        2.55       74.21
         28 |        310        3.10       77.31
         29 |        183        1.83       79.14
         30 |        244        2.44       81.58
         31 |         75        0.75       82.33
         99 |      1,767       17.67      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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