Frequencies for first 10,000 rows of surgproc variable in h126f dataset :

   WAS SURG |
       PROC |
  PERFORMED |
  ON P THIS |
      VISIT |      Freq.     Percent        Cum.
------------+-----------------------------------
         -9 |        401        4.01        4.01
         -8 |          5        0.05        4.06
         -1 |         23        0.23        4.29
          1 |      1,137       11.37       15.66
          2 |      8,434       84.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Feb 2018