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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,266       12.66       12.66
          2 |      1,123       11.23       23.89
          3 |      1,339       13.39       37.28
          4 |      1,264       12.64       49.92
          5 |        769        7.69       57.61
          6 |        545        5.45       63.06
          7 |        665        6.65       69.71
          8 |        704        7.04       76.75
          9 |        557        5.57       82.32
         10 |        561        5.61       87.93
         11 |        616        6.16       94.09
         12 |        591        5.91      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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