Frequencies for first 10,000 rows of proc23 variable in nhamcsed2000 dataset :

      other |
  procedure |
 #2 - 3 dgt |      Freq.     Percent        Cum.
------------+-----------------------------------
        000 |      9,990       99.90       99.90
        048 |          1        0.01       99.91
        389 |          1        0.01       99.92
        454 |          1        0.01       99.93
        890 |          2        0.02       99.95
        895 |          1        0.01       99.96
        942 |          1        0.01       99.97
        946 |          1        0.01       99.98
        990 |          1        0.01       99.99
        999 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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