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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,143       11.43       11.43
          2 |      1,071       10.71       22.14
          3 |      1,190       11.90       34.04
          4 |        858        8.58       42.62
          5 |        880        8.80       51.42
          6 |        848        8.48       59.90
          7 |      1,022       10.22       70.12
          8 |        675        6.75       76.87
          9 |        556        5.56       82.43
         10 |        598        5.98       88.41
         11 |        572        5.72       94.13
         12 |        587        5.87      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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