Frequencies for first 10,000 rows of ssamsasz variable in pos1996 dataset :

    ssa msa |
  size code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,689       26.89       26.89
          A |      1,450       14.50       41.39
          B |      3,027       30.27       71.66
          C |        720        7.20       78.86
          D |      1,170       11.70       90.56
          E |        815        8.15       98.71
          F |        129        1.29      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016