There's a change at the head of the T40 chart this week, as Bruno Mars' "That's What I Like" (Atlantic) slides into that coveted #1 spot. Meanwhile The Chainsmokers & Coldplay's "Something Just like This" (Disruptor/Columbia) takes a huge jump to #3 and should be the week's Greatest Gainer. Joining the Top 10 will be Julia Michaels' "Issues" (Republic) and James Arthur's "Say You Won't Let Go" (Columbia), while songs crashing the Top 20 include Ed Sheeran's "Castle On The Hill" (Atlantic) and Drake's "Passionfruit" (YMCMB/Republic). Joining the chart this week is Shawn Mendes' "There's Nothing Holdin' Me Back" (Island/Republic), Luis Fonsi & Daddy Yankee's "Despacito" f/Justin Bieber (UMLE/RBMG/DefJam/Republic) and Charlie Puth's "Attention" (Atlantic). And oh....watch out for some big releases dropping today (4/28) that are sure to shake things up!