Summary statistics for numdiffphyspdeceol variable in daphrr2011 dataset :

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
numdiffphy~l |        307    9.463847    1.945634   5.443441   14.75469

by Jean Roth , jroth@nber.org , 14 Mar 2018