Frequencies for first 10,000 rows of prov2065 variable in pos1996 dataset :

       srv: |
    alcohol |
and/or drug |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,803       88.03       88.03
          0 |        906        9.06       97.09
          1 |        215        2.15       99.24
          2 |         50        0.50       99.74
          3 |         26        0.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017