Frequencies for first 10,000 rows of bwtr4 variable in linkpe2009psden dataset :

      Birth |
     Weight |
   Recode 4 |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        138        1.38        1.38
          2 |        904        9.04       10.42
          3 |      8,957       89.57       99.99
          4 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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