Frequencies for first 10,000 rows of isllb10 variable in natl1978 dataset :

   Interval |
 since last |
 live birth |
  Recode 10 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      4,266       42.66       42.66
          1 |         94        0.94       43.60
          2 |         85        0.85       44.45
          3 |        672        6.72       51.17
          4 |        582        5.82       56.99
          5 |      1,128       11.28       68.27
          6 |        925        9.25       77.52
          7 |        618        6.18       83.70
          8 |        464        4.64       88.34
          9 |      1,078       10.78       99.12
         10 |         88        0.88      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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