Frequencies for first 10,000 rows of scopewi2 variable in nhamcsopd2004 dataset :

      scope |
  procedure |
write-in #2 |
  - 4 digit |      Freq.     Percent        Cum.
------------+-----------------------------------
       0000 |      9,981       99.81       99.81
       3142 |          1        0.01       99.82
       3323 |          2        0.02       99.84
       3324 |          1        0.01       99.85
       4513 |          3        0.03       99.88
       4516 |          1        0.01       99.89
       4523 |         10        0.10       99.99
       4921 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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