Frequencies for first 10,000 rows of tobuse variable in linkco1991us_num dataset : Tobacco use | Freq. Percent Cum. ------------+----------------------------------- 0 | 4,368 43.68 43.68 1 | 5,632 56.32 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015