Frequencies for first 10,000 rows of drugcla2 variable in nhamcsed2001 dataset :

 drug class |
for adverse |
    drug #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,939       99.39       99.39
       0626 |          2        0.02       99.41
       0627 |          1        0.01       99.42
       0628 |          1        0.01       99.43
       0630 |          2        0.02       99.45
       0631 |          2        0.02       99.47
       0874 |          1        0.01       99.48
       1180 |          1        0.01       99.49
       1373 |          1        0.01       99.50
       1374 |          3        0.03       99.53
       1727 |          2        0.02       99.55
       1944 |          1        0.01       99.56
       1945 |          1        0.01       99.57
       2000 |         19        0.19       99.76
       2087 |          8        0.08       99.84
       2210 |          1        0.01       99.85
       2220 |          9        0.09       99.94
       2230 |          1        0.01       99.95
       2250 |          4        0.04       99.99
       2260 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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