Frequencies for first 10,000 rows of segmentid variable in planreport2012 dataset :

 Segment ID |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |          6        0.06        0.06
          0 |      9,160       91.60       91.66
          1 |         88        0.88       92.54
          2 |         54        0.54       93.08
          3 |        368        3.68       96.76
          4 |        128        1.28       98.04
          5 |        104        1.04       99.08
          6 |         68        0.68       99.76
          9 |         24        0.24      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 14 Apr 2016