Frequencies for first 10,000 rows of ordperf2 variable in namcs2002 dataset :

  Surg procedure #2 - |
   ord/sched or perf? |      Freq.     Percent        Cum.
----------------------+-----------------------------------
                Blank |      9,846       98.46       98.46
    Ordered/scheduled |         57        0.57       99.03
            Performed |         67        0.67       99.70
              Unknown |         30        0.30      100.00
----------------------+-----------------------------------
                Total |     10,000      100.00

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