Frequencies for first 10,000 rows of prescr3 variable in namcs1993 dataset :

prescriptio |
   n status |
   code for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,500       15.00       15.00
          2 |        190        1.90       16.90
          3 |        130        1.30       18.20
          . |      8,180       81.80      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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