Frequencies for first 10,000 rows of mri variable in namcs2008 dataset : mri | Freq. Percent Cum. ------------+----------------------------------- no | 9,868 98.68 98.68 yes | 132 1.32 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016