Frequencies for first 10,000 rows of prov6185 variable in pos2009 dataset :

 SRV: SHOCK |
       WAVE |
LITHOTRIPTE |
          R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,638       86.38       86.38
          0 |      1,285       12.85       99.23
          1 |         17        0.17       99.40
          2 |         47        0.47       99.87
          3 |         13        0.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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