Frequencies for first 10,000 rows of birwt4 variable in natlterr2001 dataset :

      Birth |
     Weight |
   Recode 4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        148        1.48        1.48
          2 |        978        9.78       11.26
          3 |      8,870       88.70       99.96
          4 |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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