Frequencies for first 10,000 rows of bwtr4 variable in natlterr2005 dataset :

      Birth |
     Weight |
   Recode 4 |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        114        1.14        1.14
          2 |        801        8.01        9.15
          3 |      9,052       90.52       99.67
          4 |         33        0.33      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015