Frequencies for first 10,000 rows of prescr3 variable in namcs1997 dataset :

prescriptio |
   n status |
   code for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,521       25.21       25.21
          2 |        353        3.53       28.74
          3 |        157        1.57       30.31
          . |      6,969       69.69      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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