Frequencies for first 10,000 rows of injury variable in nhamcsed1998 dataset : is visit | related to | injury or | poisoning? | Freq. Percent Cum. ------------+----------------------------------- 0 | 6,605 66.05 66.05 1 | 3,395 33.95 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016