Summary statistics for numdiffphyspdeceol variable in daphosp2009 dataset :

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
numdiffphy~l |      2,600    10.56255    2.715682    3.58921   19.47384

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