Frequencies for first 10,000 rows of drugcl4 variable in nhamcsed1992 dataset :

 Drug class |
for drug #4 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,480       94.80       94.80
         01 |         30        0.30       95.10
         02 |          1        0.01       95.11
         03 |         53        0.53       95.64
         04 |         14        0.14       95.78
         05 |         73        0.73       96.51
         06 |         34        0.34       96.85
         08 |         38        0.38       97.23
         09 |         30        0.30       97.53
         10 |         19        0.19       97.72
         11 |          4        0.04       97.76
         12 |         17        0.17       97.93
         13 |         13        0.13       98.06
         15 |          4        0.04       98.10
         16 |          1        0.01       98.11
         17 |         81        0.81       98.92
         18 |          1        0.01       98.93
         19 |         80        0.80       99.73
         20 |         27        0.27      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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