Frequencies for first 10,000 rows of urine variable in nhamcsopd1997 dataset : urinalysis | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,831 88.31 88.31 1 | 1,169 11.69 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016