Frequencies for zip_class variable in zipmil_12q4 dataset : zip code | classificat | ion:p=po | box | u=unique | zip used | for large | orgs/busine | sses/bld | Freq. Percent Cum. ------------+----------------------------------- M | 538 100.00 100.00 ------------+----------------------------------- Total | 538 100.00 by Jean Roth , jroth@nber.org , 4 Jan 2016 tail -n+3 /homes/data/zip/sas/2012/desc/zipmil_12q4/byvar/tab/zip_class.log |