Frequencies for first 10,000 rows of prescr3 variable in nhamcsed1997 dataset :

prescriptio |
   n status |
   code for |
    drug #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,356       13.56       13.56
          2 |        302        3.02       16.58
          3 |        200        2.00       18.58
          . |      8,142       81.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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