Summary statistics for a7_3_c11_2 variable in hosp_rollup2552_96_2011 dataset :

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
  a7_3_c11_2 |          1          -1           .         -1         -1

by Jean Roth , jroth@nber.org , 21 Apr 2018