Frequencies for first 10,000 rows of cmsa variable in natl1991 dataset :

    CMSA of |
  Residence |
     (FIPS) |      Freq.     Percent        Cum.
------------+-----------------------------------
         00 |      9,998       99.98       99.98
         31 |          1        0.01       99.99
         49 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015