Frequencies for first 10,000 rows of amb22 variable in nhamcsopd1997 dataset :

 ambulatory |
       surg |
  procedure |
 #2 - 2 dgt |      Freq.     Percent        Cum.
------------+-----------------------------------
         00 |      9,960       99.60       99.60
         12 |          1        0.01       99.61
         13 |          1        0.01       99.62
         42 |          1        0.01       99.63
         48 |          1        0.01       99.64
         49 |          1        0.01       99.65
         53 |          1        0.01       99.66
         59 |          1        0.01       99.67
         66 |          2        0.02       99.69
         67 |          2        0.02       99.71
         68 |          4        0.04       99.75
         69 |          2        0.02       99.77
         70 |          1        0.01       99.78
         80 |          3        0.03       99.81
         81 |          2        0.02       99.83
         83 |          1        0.01       99.84
         86 |          2        0.02       99.86
         88 |          4        0.04       99.90
         89 |          1        0.01       99.91
         91 |          2        0.02       99.93
         93 |          2        0.02       99.95
         97 |          4        0.04       99.99
         99 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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