Frequencies for first 10,000 rows of prov1965 variable in pos1991 dataset :

        400 |
 hematology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,536       85.36       85.36
          N |        520        5.20       90.56
          Y |        944        9.44      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016