Summary statistics for psych_unit_efctv_dt variable in pos2014 dataset : Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- psych_u~v_dt | 2,322 1.99e+07 90794.18 1.98e+07 2.02e+07 by Jean Roth , jroth@nber.org , 26 Jan 2016