"Deadly Attacks Since 9/11" it says. If this done for 15 years what would those numbers be? If you want to tabulate something similar for the number American troops killed in foreign lands, you could do it since Vietnam, or since WWII, if you want to fudge the numbers for more extended time, which is what this junk does.
BTW where are the numbers killed in automobile collisions-- all kinds? That would be a lot more than the number "Being Shot By Another American." This is obviously meant to indicate the greatest danger is guns in America. This is significant, or not so, to the individual. But it does show how selective these numbers are.