Frequencies for first 10,000 rows of birday variable in natl1978 dataset :

 Birth Date |
      - Day |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        412        4.12        4.12
          2 |        344        3.44        7.56
          3 |        371        3.71       11.27
          4 |        338        3.38       14.65
          5 |        346        3.46       18.11
          6 |        374        3.74       21.85
          7 |        358        3.58       25.43
          8 |        365        3.65       29.08
          9 |        348        3.48       32.56
         10 |        355        3.55       36.11
         11 |        333        3.33       39.44
         12 |        333        3.33       42.77
         13 |        352        3.52       46.29
         14 |        372        3.72       50.01
         15 |        330        3.30       53.31
         16 |        385        3.85       57.16
         17 |        339        3.39       60.55
         18 |        306        3.06       63.61
         19 |        310        3.10       66.71
         20 |        339        3.39       70.10
         21 |        293        2.93       73.03
         22 |        308        3.08       76.11
         23 |        326        3.26       79.37
         24 |        328        3.28       82.65
         25 |        315        3.15       85.80
         26 |        327        3.27       89.07
         27 |        300        3.00       92.07
         28 |        266        2.66       94.73
         29 |        162        1.62       96.35
         30 |        189        1.89       98.24
         31 |        176        1.76      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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