Frequencies for first 10,000 rows of ssamsasz variable in pos1993 dataset :

    ssa msa |
  size code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,263       22.63       22.63
          A |      1,643       16.43       39.06
          B |      3,211       32.11       71.17
          C |        818        8.18       79.35
          D |      1,210       12.10       91.45
          E |        739        7.39       98.84
          F |        116        1.16      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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