Frequencies for first 10,000 rows of pctpovr variable in nhamcsed2009 dataset :

percent pop |
      below |
    poverty |
   level in |
  patient's |
   zip code |      Freq.     Percent        Cum.
------------+-----------------------------------
         -9 |        715        7.15        7.15
          1 |      1,313       13.13       20.28
          2 |      2,490       24.90       45.18
          3 |      3,158       31.58       76.76
          4 |      2,324       23.24      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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