Once upon a time, music fans bought hundreds of millions of CDs each year, fueling lavish industry profits. Nowadays, with streaming the dominant format — but with each click bringing infinitesimal royalties — artists and their record companies must come up with all sorts of gimmicks to sell those gleaming plastic discs, which can help boost an album’s position on the weekly Billboard chart.

Over the last couple of months, the chart has been a showcase of some ingenious tactics. Taylor Swift offered four deluxe versions of her album “Lover” at Target stores, while the metal band Tool sold 88,000 CDs in its first week as part of a $45 foldout package that included a four-inch HD video screen.

But now a K-pop supergroup has truly pushed the envelope: SuperM — a seven-member boy band whose existence was announced just two months ago — topped Billboard’s latest album chart with a seven-track EP that was sold in an array of CD versions and bundle deals.

SuperM’s debut, “The 1st Mini Album ‘SuperM’,” opened at No. 1 with 164,000 album sales and a modest 4.9 million streams, according to Nielsen. Of those album sales, 113,000 were CDs and 51,000 were digital downloads.