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

  Peak flow |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,994       99.94       99.94
        Yes |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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