Frequencies for first 10,000 rows of prov6185 variable in pos2006 dataset :

 srv: shock |
       wave |
lithotripte |
          r |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,710       87.10       87.10
          0 |      1,263       12.63       99.73
          1 |          6        0.06       99.79
          2 |         18        0.18       99.97
          3 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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