Well, they are referring to the Billboard Hot 100, but they've got to be misinterpreting the information or something. "Toxic" only peaked at number nine. "Circus," I don't remember the exact number, but I think it went top three or top five. They might be thinking of the Hot Digital Songs then, but I don't know "Toxic"'s run on that chart. Actually, now that I think about it, "Toxic" couldn't of hit number one there as that chart wasn't around until 2005. "Toxic" was out in 2003. Maybe Top 40 Mainstream or Pop 100 then?