Frequencies for first 10,000 rows of proc43d variable in namcs1993 dataset :

 service #4 |
  procedure |
   code - 3 |
     digits |      Freq.     Percent        Cum.
------------+-----------------------------------
        000 |      9,945       99.45       99.45
        039 |          1        0.01       99.46
        372 |          1        0.01       99.47
        381 |          1        0.01       99.48
        451 |          1        0.01       99.49
        702 |          1        0.01       99.50
        873 |          3        0.03       99.53
        874 |          2        0.02       99.55
        876 |          3        0.03       99.58
        882 |          1        0.01       99.59
        883 |          1        0.01       99.60
        887 |          6        0.06       99.66
        892 |          1        0.01       99.67
        893 |          3        0.03       99.70
        894 |          1        0.01       99.71
        895 |          3        0.03       99.74
        896 |          1        0.01       99.75
        914 |          1        0.01       99.76
        920 |          1        0.01       99.77
        921 |          1        0.01       99.78
        931 |         16        0.16       99.94
        933 |          1        0.01       99.95
        935 |          2        0.02       99.97
        936 |          2        0.02       99.99
        950 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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