Frequencies for first 10,000 rows of drug3cl3 variable in namcs2004 dataset :

ndc code #3 |
        for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,919       99.19       99.19
       0514 |          4        0.04       99.23
       0877 |          1        0.01       99.24
       1374 |          8        0.08       99.32
       1568 |          2        0.02       99.34
       1728 |         52        0.52       99.86
       1864 |          2        0.02       99.88
       1943 |          2        0.02       99.90
       1944 |          6        0.06       99.96
       1945 |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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