Frequencies for first 10,000 rows of nlbnd variable in natl1972 dataset :

 Born alive |
 - now dead |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,491       94.91       94.91
          1 |        379        3.79       98.70
          2 |         48        0.48       99.18
          3 |          9        0.09       99.27
          4 |          5        0.05       99.32
          6 |          2        0.02       99.34
         20 |          1        0.01       99.35
         55 |          2        0.02       99.37
         66 |          3        0.03       99.40
         77 |         34        0.34       99.74
         99 |         26        0.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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