Frequencies for first 10,000 rows of segmentid variable in ma2007 dataset :

 Segment ID |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,925       99.25       99.25
          1 |         14        0.14       99.39
          2 |         35        0.35       99.74
          3 |         26        0.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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