Frequencies for first 10,000 rows of bwimp variable in natl1995 dataset :

    Imputed |
Birthweight |      Freq.     Percent        Cum.
------------+-----------------------------------
        680 |          1        0.01        0.01
       9999 |          1        0.01        0.02
          . |      9,998       99.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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