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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,174       11.74       11.74
          2 |      1,185       11.85       23.59
          3 |      1,232       12.32       35.91
          4 |      1,152       11.52       47.43
          5 |        927        9.27       56.70
          6 |        684        6.84       63.54
          7 |        741        7.41       70.95
          8 |        627        6.27       77.22
          9 |        529        5.29       82.51
         10 |        642        6.42       88.93
         11 |        613        6.13       95.06
         12 |        494        4.94      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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