Frequencies for first 10,000 rows of prescra2 variable in nhamcsed2002 dataset :

prescriptio |
   n status |
   code for |
    adverse |
    drug #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         37        0.37        0.37
          2 |          3        0.03        0.40
          3 |          7        0.07        0.47
          4 |         23        0.23        0.70
          . |      9,930       99.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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