Summary statistics for partdpremiumobligationwith50prem variable in planreport2010 dataset :

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
partdp~0prem |    252,798    20.27061    50.10047          0       1233

by Jean Roth , jroth@nber.org , 14 Apr 2016