Frequencies for first 10,000 rows of sex variable in nhamcsopd1999 dataset : patient sex | Freq. Percent Cum. ------------+----------------------------------- Female | 6,399 63.99 63.99 Male | 3,601 36.01 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016