Frequencies for first 10,000 rows of blodpres variable in namcs1996 dataset : blood | pressure | test | Freq. Percent Cum. ------------+----------------------------------- 0 | 5,450 54.50 54.50 1 | 4,550 45.50 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016