Frequencies for first 10,000 rows of subst variable in namcs2014 dataset :

  Substance |
      abuse |
  screening |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,873       98.73       98.73
        Yes |        127        1.27      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017