Summary statistics for ppefaddr dataset : by Jean Roth , jroth@nber.org , 15 Apr 2019 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- enrlmt_id | 0 city_name | 0 zip_cd | 989,534 4.60e+08 3.04e+08 0 1.00e+09 state_cd | 989,534 27.81204 15.51492 1 70 state_cdstr | 0 by Jean Roth , jroth@nber.org , 15 Apr 2019