Frequencies for first 10,000 rows of cbc variable in nhamcsed2010 dataset : cbc | Freq. Percent Cum. ------------+----------------------------------- no | 6,181 61.81 61.81 yes | 3,819 38.19 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016