Frequencies for first 10,000 rows of proc23 variable in nhamcsed1996 dataset :

      other |
  procedure |
 #2 - 3 dgt |      Freq.     Percent        Cum.
------------+-----------------------------------
        000 |      9,988       99.88       99.88
        393 |          1        0.01       99.89
        429 |          1        0.01       99.90
        681 |          1        0.01       99.91
        860 |          2        0.02       99.93
        873 |          1        0.01       99.94
        896 |          1        0.01       99.95
        914 |          1        0.01       99.96
        939 |          1        0.01       99.97
        990 |          1        0.01       99.98
        999 |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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