Frequencies for first 10,000 rows of ssamsasz variable in pos2004 dataset :

    ssa msa |
  size code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,977       29.77       29.77
          A |      1,454       14.54       44.31
          B |      2,658       26.58       70.89
          C |        787        7.87       78.76
          D |      1,190       11.90       90.66
          E |        787        7.87       98.53
          F |        147        1.47      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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