Frequencies for first 10,000 rows of ssamsasz variable in pos1998 dataset :

    ssa msa |
  size code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,664       26.64       26.64
          A |      1,571       15.71       42.35
          B |      2,938       29.38       71.73
          C |        776        7.76       79.49
          D |      1,183       11.83       91.32
          E |        735        7.35       98.67
          F |        133        1.33      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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