Frequencies for first 10,000 rows of prescr3 variable in namcs2002 dataset :

 Prescription status |
 code for medication |
                  #3 |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   Prescription drug |      1,712       17.12       17.12
Nonprescription drug |        172        1.72       18.84
        Undetermined |        131        1.31       20.15
                   . |      7,985       79.85      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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