Frequencies for first 10,000 rows of bwtr4 variable in natl2012 dataset :

      Birth |
     Weight |
   Recode 4 |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         75        0.75        0.75
          2 |        461        4.61        5.36
          3 |      9,448       94.48       99.84
          4 |         16        0.16      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 5 May 2016