Frequencies for first 10,000 rows of urine variable in nhamcsopd2001 dataset : urinalysis | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,920 89.20 89.20 1 | 1,080 10.80 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016