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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,200       12.00       12.00
          2 |      1,127       11.27       23.27
          3 |      1,281       12.81       36.08
          4 |      1,243       12.43       48.51
          5 |      1,137       11.37       59.88
          6 |        538        5.38       65.26
          7 |        687        6.87       72.13
          8 |        554        5.54       77.67
          9 |        569        5.69       83.36
         10 |        632        6.32       89.68
         11 |        486        4.86       94.54
         12 |        546        5.46      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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