Frequencies for first 10,000 rows of examwi2 variable in namcs2002 dataset :

       Exam |
write-in #2 |
  - 4 digit |      Freq.     Percent        Cum.
------------+-----------------------------------
       0000 |      9,647       96.47       96.47
       8913 |         12        0.12       96.59
       8926 |         89        0.89       97.48
       8929 |          1        0.01       97.49
       8931 |          1        0.01       97.50
       8934 |         26        0.26       97.76
       8936 |         22        0.22       97.98
       8939 |        181        1.81       99.79
       8965 |          1        0.01       99.80
       897- |          4        0.04       99.84
       9304 |          2        0.02       99.86
       9305 |          7        0.07       99.93
       9402 |          2        0.02       99.95
       9411 |          1        0.01       99.96
       9419 |          1        0.01       99.97
       9509 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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