Frequencies for first 10,000 rows of otherbld variable in nhamcsopd1995 dataset : other blood | test | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,102 81.02 81.02 1 | 1,898 18.98 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016