Song mentions are tracked through several means, according to Billboard. These include:

• The use of, or the inclusion, of a link to the song via music listening platforms, such as Spotify, Vevo and iTunes.
• The use of various track sharing notations, such as the hashtags “#nowplaying” or “#np,” along with song/artist name.
• The use of various terms associated with the song and song playing, such as “music,” “song,” “track,” “listen.”

This results in two charts: the Trending 140, which ranks songs shared in the US and is measured by acceleration over the past hour; and Emerging Artists, which ranks the most shared songs by up and coming artists, based on the number of times the song was shared over the past 24 hours.

Lana Del Rey is currently topping the Trending 140, with Ultraviolence, the title track of her upcoming new album, while Ransom’s Dying Breed is number one on the Emerging Artists chart.

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