Frequencies for first 10,000 rows of prov1935 variable in pos1993 dataset :

        300 |
  chemistry |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,797       87.97       87.97
          N |        621        6.21       94.18
          Y |        582        5.82      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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