Frequencies for first 10,000 rows of prescr6 variable in nhamcsed1997 dataset :

prescriptio |
   n status |
   code for |
    drug #6 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        175        1.75        1.75
          2 |         23        0.23        1.98
          3 |         19        0.19        2.17
          . |      9,783       97.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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