Frequencies for first 10,000 rows of prescr3 variable in nhamcsopd1998 dataset :

prescriptio |
   n status |
   code for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,638       16.38       16.38
          2 |        253        2.53       18.91
          3 |        138        1.38       20.29
          . |      7,971       79.71      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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