Frequencies for first 10,000 rows of prov2070 variable in pos1997 dataset :

       srv: |
 anesthesia |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,792       87.92       87.92
          0 |        395        3.95       91.87
          1 |        415        4.15       96.02
          2 |        348        3.48       99.50
          3 |         50        0.50      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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