Frequencies for first 10,000 rows of ordperf2 variable in nhamcsopd2001 dataset :

       surg |
  procedure |
       #2 - |
  ord/sched |
   or perf? |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,932       99.32       99.32
          1 |         26        0.26       99.58
          2 |         38        0.38       99.96
          9 |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016