Frequencies for first 10,000 rows of shck_trma_srvc_cd variable in pos2007 dataset :

srv: trauma |
     center |
(certified) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,682       86.82       86.82
          0 |      1,219       12.19       99.01
          1 |         68        0.68       99.69
          2 |         23        0.23       99.92
          3 |          8        0.08      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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