Frequencies for first 10,000 rows of injury variable in nhamcsed1999 dataset : is visit | related to | injury or | poisoning? | Freq. Percent Cum. ------------+----------------------------------- 0 | 6,541 65.41 65.41 1 | 3,459 34.59 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016