Frequencies for first 10,000 rows of catscan variable in nhamcsopd2008 dataset : ct scan | Freq. Percent Cum. ------------+----------------------------------- no | 9,762 97.62 97.62 yes | 238 2.38 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016