Summary statistics for ziphsahrr2004 dataset : by Jean Roth , jroth@nber.org , 14 Mar 2018 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- zipcode | 0 hsanum | 41,272 26748.29 15051.83 1001 53026 hsacity | 0 hsastate | 0 hrrnum | 41,272 258.1705 122.4364 1 457 -------------+--------------------------------------------------------- hrrcity | 0 hrrstate | 0 year | 41,272 2004 0 2004 2004 by Jean Roth , jroth@nber.org , 14 Mar 2018