Frequencies for first 10,000 rows of toxclgy variable in person dataset :

 Drug Noted |
         in |
 Toxicology |
     Report |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,407       54.07       54.07
          1 |      1,695       16.95       71.02
          2 |        167        1.67       72.69
          3 |        709        7.09       79.78
          7 |          7        0.07       79.85
          8 |      1,749       17.49       97.34
          9 |        266        2.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016