Frequencies for first 10,000 rows of month variable in person dataset :

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,166       11.66       11.66
          2 |      1,155       11.55       23.21
          3 |      1,441       14.41       37.62
          4 |      1,375       13.75       51.37
          5 |        900        9.00       60.37
          6 |        636        6.36       66.73
          7 |        637        6.37       73.10
          8 |        571        5.71       78.81
          9 |        502        5.02       83.83
         10 |        549        5.49       89.32
         11 |        586        5.86       95.18
         12 |        482        4.82      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016