Frequencies for first 10,000 rows of precare variable in linkpe2009psden dataset :

      Month |
   Prenatal |
 Care Began |
  R (f_mpcb |
  rep flag) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         12        0.12        0.12
          1 |        464        4.64        4.76
          2 |      2,255       22.55       27.31
          3 |      2,078       20.78       48.09
          4 |        938        9.38       57.47
          5 |        429        4.29       61.76
          6 |        224        2.24       64.00
          7 |         86        0.86       64.86
          8 |         54        0.54       65.40
          9 |          9        0.09       65.49
         10 |          2        0.02       65.51
         99 |         27        0.27       65.78
          . |      3,422       34.22      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015