Frequencies for first 10,000 rows of eeg variable in namcs2012 dataset :

Electroence |
  phalogram |
      (EEG) |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,985       99.85       99.85
        Yes |         15        0.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016