Frequencies for first 10,000 rows of otherbld variable in nhamcsopd1997 dataset : other blood | test | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,058 80.58 80.58 1 | 1,942 19.42 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016