Frequencies for first 10,000 rows of precare variable in natl2014 dataset :

      Month |
   Prenatal |
 Care Began |
      00 No |
   prenatal |
       care |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         81        0.81        0.81
          1 |        283        2.83        3.64
          2 |      3,328       33.28       36.92
          3 |      3,300       33.00       69.92
          4 |      1,017       10.17       80.09
          5 |        606        6.06       86.15
          6 |        307        3.07       89.22
          7 |        254        2.54       91.76
          8 |        205        2.05       93.81
          9 |         85        0.85       94.66
         10 |          1        0.01       94.67
         99 |        533        5.33      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016