Frequencies for first 10,000 rows of bwtr12 variable in natl2007 dataset :

      Birth |
     Weight |
  Recode 12 |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          4        0.04        0.04
          2 |         33        0.33        0.37
          3 |         51        0.51        0.88
          4 |        120        1.20        2.08
          5 |        345        3.45        5.53
          6 |      1,329       13.29       18.82
          7 |      3,532       35.32       54.14
          8 |      3,242       32.42       86.56
          9 |      1,062       10.62       97.18
         10 |        219        2.19       99.37
         11 |         23        0.23       99.60
         12 |         40        0.40      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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