Frequencies for first 10,000 rows of blodpres variable in namcs2007 dataset : blood | pressure | taken | Freq. Percent Cum. ------------+----------------------------------- no | 3,143 31.43 31.43 yes | 6,857 68.57 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016