Frequencies for first 10,000 rows of msa variable in natl2004 dataset :

Metropolita |
          n |
Statistical |
   Area U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          3        0.03        0.03
         40 |          1        0.01        0.04
        120 |          1        0.01        0.05
        380 |      4,258       42.58       42.63
        440 |          1        0.01       42.64
        520 |          1        0.01       42.65
       2080 |          1        0.01       42.66
       2840 |          1        0.01       42.67
       3000 |          1        0.01       42.68
       3283 |          1        0.01       42.69
       3320 |          1        0.01       42.70
       4480 |          1        0.01       42.71
       5120 |          1        0.01       42.72
       6520 |          2        0.02       42.74
       9360 |          1        0.01       42.75
       9999 |      5,725       57.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 21 Jan 2016