Frequencies for first 10,000 rows of isllb8 variable in natl1983 dataset :

   Interval |
 since last |
 live birth |
   Recode 8 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      4,344       43.44       43.44
          1 |        110        1.10       44.54
          2 |         86        0.86       45.40
          3 |      1,331       13.31       58.71
          4 |      1,184       11.84       70.55
          5 |        897        8.97       79.52
          6 |        946        9.46       88.98
          7 |      1,016       10.16       99.14
          8 |         86        0.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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