Frequencies for first 10,000 rows of ivfluids variable in nhamcsed1993 dataset : iv fluids | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,434 84.34 84.34 1 | 1,566 15.66 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016