Frequencies for first 10,000 rows of proc53d variable in namcs2009 dataset :

procedure 5 |
  - 2 digit |      Freq.     Percent        Cum.
------------+-----------------------------------
         -9 |      9,995       99.95       99.95
        891 |          2        0.02       99.97
        893 |          1        0.01       99.98
        950 |          1        0.01       99.99
        994 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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