Frequencies for first 10,000 rows of prescr4 variable in nhamcsopd1993 dataset :

prescriptio |
   n status |
   code for |
 medication |
         #4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        688        6.88        6.88
          2 |        145        1.45        8.33
          3 |        125        1.25        9.58
          . |      9,042       90.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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