Frequencies for first 10,000 rows of prescr3 variable in nhamcsed1993 dataset :

prescriptio |
   n status |
   code for |
    drug #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,220       12.20       12.20
          2 |        277        2.77       14.97
          3 |        189        1.89       16.86
          . |      8,314       83.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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