Frequencies for first 10,000 rows of prescr2 variable in nhamcsed1996 dataset :

prescriptio |
   n status |
   code for |
    drug #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,745       27.45       27.45
          2 |        683        6.83       34.28
          3 |        458        4.58       38.86
          . |      6,114       61.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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