Frequencies for first 10,000 rows of hincomer variable in nhamcsed2008 dataset :

  median household income in |
          patient's zip code |      Freq.     Percent        Cum.
-----------------------------+-----------------------------------
                missing data |        563        5.63        5.63
  quartile 1 (below $32,793) |      2,750       27.50       33.13
quartile 2 ($32,794-$40,626) |      2,696       26.96       60.09
quartile 3 ($40,627-$52,387) |      2,013       20.13       80.22
quartile 4 ($52,388 or more) |      1,978       19.78      100.00
-----------------------------+-----------------------------------
                       Total |     10,000      100.00

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