Frequencies for first 10,000 rows of pbamorer variable in namcs2008 dataset :

  percent pop w/bachelor's degree or |
             higher in patient's zip |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                        missing data |        478        4.78        4.78
quartile 1 (less than 12.84 percent) |      2,067       20.67       25.45
    quartile 2 (12.84-19.66 percent) |      2,555       25.55       51.00
    quartile 3 (19.67-31.68 percent) |      2,547       25.47       76.47
  quartile 4 (31.69 percent or more) |      2,353       23.53      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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