Frequencies for first 10,000 rows of scopewi2 variable in namcs2005 dataset :

      scope |
  procedure |
         #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
       0000 |      9,990       99.90       99.90
       4432 |          1        0.01       99.91
       4513 |          4        0.04       99.95
       4523 |          4        0.04       99.99
       9999 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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