Frequencies for first 10,000 rows of prescr4 variable in nhamcsopd1994 dataset :

prescriptio |
   n status |
   code for |
 medication |
         #4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        645        6.45        6.45
          2 |        106        1.06        7.51
          3 |         88        0.88        8.39
          . |      9,161       91.61      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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