Frequencies for first 10,000 rows of segmentid variable in ma2011 dataset :

 Segment ID |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |          6        0.06        0.06
          0 |      9,047       90.47       90.53
          1 |        104        1.04       91.57
          2 |         53        0.53       92.10
          3 |        412        4.12       96.22
          4 |        168        1.68       97.90
          5 |        117        1.17       99.07
          6 |         78        0.78       99.85
          9 |         15        0.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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