Frequencies for first 10,000 rows of telephon variable in nhamcsopd2005 dataset : telephone | follow up | Freq. Percent Cum. ------------+----------------------------------- no | 9,788 97.88 97.88 yes | 212 2.12 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016