Frequencies for first 10,000 rows of mpre6 variable in natl1982 dataset :

      Month |
   Prenatal |
 Care began |
   Recode 6 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      4,805       48.05       48.05
          2 |      2,296       22.96       71.01
          3 |      2,162       21.62       92.63
          4 |        499        4.99       97.62
          5 |        191        1.91       99.53
          6 |         47        0.47      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016