Frequencies for first 10,000 rows of urbanrur variable in nhamcsed2006 dataset :

        urban-rural classification of |
                   patient's zip code |      Freq.     Percent        Cum.
--------------------------------------+-----------------------------------
                  large central metro |      2,778       27.78       27.78
                   large fringe metro |      2,644       26.44       54.22
                         medium metro |      2,214       22.14       76.36
                          small metro |        907        9.07       85.43
non-metro (micropolitan and non-core) |      1,164       11.64       97.07
                         missing data |        293        2.93      100.00
--------------------------------------+-----------------------------------
                                Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016