One Direction is the only group to have at least one member hit No. 1 solo ... and now three have.
Niall Horan is the top musical act in the U.S., as the pop singer-songwriter leaps 24-1 on the Billboard Artist 100 chart (dated Nov. 11). Horan follows Zayn and Harry Styles as the third member of One Direction to top the list.
Aside from One Direction (which peaked at No. 2 in December 2014), no other group has seen any of its members rule the Artist 100, never mind three.
The Artist 100, which launched in July 2014, measures artist activity across key metrics of music consumption, blending album and track sales, radio airplay, streaming and social media fan interaction to provide a weekly multi-dimensional ranking of artist popularity.