Frequencies for dst variable in zipmil_12q4 dataset : zip code | obeys | daylight | savings: | y-yes n-no | Freq. Percent Cum. ------------+----------------------------------- N | 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/dst.log | egrep