Frequencies for first 10,000 rows of prov2420 variable in pos2001 dataset :

       srv: |
psychologic |
         al |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,904       99.04       99.04
          0 |         45        0.45       99.49
          1 |         12        0.12       99.61
          2 |         20        0.20       99.81
          3 |         19        0.19      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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