16. Julia Michaels, "Uh Huh"
Michaels is an indispensable Top 40 songwriter – that's her in the credits of the Selena Gomez song coming up at Number 12. She's just as dazzling front and center on this breathless ode to an affair that's much too hot to take it slow. "It's rare when the panic in my mind feels so damn good," she gasps. The song's damn good, too.