Frequencies for first 10,000 rows of open_hrt_srgry_srvc_cd variable in pos1991 dataset :

  srv: open |
      heart |
    surgery |
   facility |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,770       87.70       87.70
          0 |        979        9.79       97.49
          1 |        184        1.84       99.33
          2 |         65        0.65       99.98
          3 |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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