Frequencies for first 10,000 rows of prov2520 variable in pos1997 dataset :

srv: speech |
    therapy |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,629       86.29       86.29
          0 |        264        2.64       88.93
          1 |        305        3.05       91.98
          2 |        605        6.05       98.03
          3 |        197        1.97      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016