Frequencies for first 10,000 rows of ca_omph variable in natlterr2005 dataset : Omphalocele | R | Freq. Percent Cum. ------------+----------------------------------- | 6,255 62.55 62.55 N | 3,745 37.45 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015