We have a new #1 this week at T40 as Major Lazer's "Cold Water" f/Justin Bieber & MØ (Mad Decent/Def Jam) takes their turn at the top. But hot on their tail is The Chainsmokers' "Closer " f/Halsey (Disruptor/Columbia), which explodes from #6 to #2 and is on pace to become the Greatest Gainer this week. Ariana Grande's "Into You" (Republic) moves up a notch to #7 while label mate Hailee Steinfeld's "Starving" f/Grey looks to join the Top 20. Jon Bellion's "All Time Low" (Capitol) takes a big jump up and climbs into the Top 30. And charting this week will be Tove Lo's "Cool Girl" (Island/Republic) and Jason Derulo's "Kiss The Sky" (Warner Bros.)