Frequencies for first 10,000 rows of pbamorer variable in nhamcsopd2009 dataset :

    recoded percent pop w/bachelor's |
   degree or higher in patient's zip |
                                code |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                        missing data |        480        4.80        4.80
quartile 1 (less than 12.84 percent) |      2,534       25.34       30.14
    quartile 2 (12.84-19.66 percent) |      2,694       26.94       57.08
    quartile 3 (19.67-31.68 percent) |      2,254       22.54       79.62
  quartile 4 (31.69 percent or more) |      2,038       20.38      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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