Things just keep getting better for 5 Seconds of Summer. The Australian band's latest hit, "Youngblood," has risen to #1 on Billboard's Pop Songs chart, which measures radio airplay. It's the latest milestone for the band -- last week, "Youngblood" became their first top-10 on the Billboard Hot 100, which measures sales, streaming and airplay. Previously, 5SoS had gotten as high as #15 with their 2015 single, "She's Kinda Hot." They also went top 20 with 2014's "She Looks So Perfect" and "Amnesia." The band wrote on Instagram, "We can’t make it without you//Today 5 Seconds Of Summer are Number 1 on US radio, today is an Incredible day." Copyright © 2018, ABC Radio. All rights reserved.