Frequencies for first 10,000 rows of herpes variable in natlterr1994 dataset : Herpes | Freq. Percent Cum. ------------+----------------------------------- 1 | 15 0.15 0.15 2 | 9,973 99.73 99.88 9 | 12 0.12 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015