Frequencies for first 10,000 rows of prescr2 variable in nhamcsed2000 dataset :

prescriptio |
   n status |
   code for |
    drug #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,771       27.71       27.71
          2 |        683        6.83       34.54
          3 |        568        5.68       40.22
          . |      5,978       59.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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