Frequencies for first 10,000 rows of drug3cl3 variable in nhamcsopd2002 dataset :

 drug class |
     #3 for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,938       99.38       99.38
       0514 |          2        0.02       99.40
       0915 |          1        0.01       99.41
       1275 |          2        0.02       99.43
       1374 |          7        0.07       99.50
       1568 |          1        0.01       99.51
       1728 |         44        0.44       99.95
       1940 |          1        0.01       99.96
       1944 |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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