Summary statistics for sf12010zcta5distance50miles dataset :

by Jean Roth , jroth@nber.org , 4 Jan 2016

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
        zip1 |          0
        zip2 |          0
 mi_to_zcta5 | 13,082,844    50.49158    20.38321   .0493327    80.4672

by Jean Roth , jroth@nber.org , 4 Jan 2016