Frequencies for first 10,000 rows of stress variable in nhamcsopd1998 dataset : stress | management | couns/educ | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,705 97.05 97.05 1 | 295 2.95 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016