Frequencies for first 10,000 rows of birmon variable in natl2000 dataset :

   Month of |
      Birth |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      5,131       51.31       51.31
          2 |      4,614       46.14       97.45
          3 |        255        2.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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