Frequencies for first 10,000 rows of allertst variable in nhamcsopd1994 dataset : allergy | testing | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,985 99.85 99.85 1 | 15 0.15 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016