Frequencies for first 10,000 rows of isllb17 variable in natl1983 dataset :

   Interval |
 since last |
 live birth |
  Recode 17 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      4,344       43.44       43.44
          1 |        110        1.10       44.54
          2 |         86        0.86       45.40
          4 |        312        3.12       48.52
          5 |        374        3.74       52.26
          7 |        355        3.55       55.81
          8 |        290        2.90       58.71
         10 |        617        6.17       64.88
         11 |        567        5.67       70.55
         12 |        897        8.97       79.52
         13 |        576        5.76       85.28
         14 |        370        3.70       88.98
         16 |        282        2.82       91.80
         17 |        199        1.99       93.79
         18 |        154        1.54       95.33
         19 |        121        1.21       96.54
         20 |        260        2.60       99.14
         21 |         86        0.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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