Frequencies for first 10,000 rows of ctab variable in nhamcsed2014 dataset : CT scan - | abdomen/pel | vis | Freq. Percent Cum. ------------+----------------------------------- No | 9,435 94.35 94.35 Yes | 565 5.65 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 11 Apr 2017