Frequencies for first 10,000 rows of prov2420 variable in pos2006 dataset :

       srv: |
psychologic |
         al |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,863       98.63       98.63
          0 |         82        0.82       99.45
          1 |         13        0.13       99.58
          2 |         22        0.22       99.80
          3 |         20        0.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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