A paradox of the new music industry: Albums sell less and less well every year, but as a marketing tool they are now more important than ever.

A case in point is Lady Gaga, whose new album, “Born This Way” (Interscope), was released on May 23 and sold 1,108,000 copies in the United States in its first week, according to Nielsen SoundScan. Some 662,000 of those sales, or about 60 percent, were digital downloads, the most any album has ever sold in a week.

The extraordinary success of “Born This Way” — it outsold the next 42 albums on Billboard’s chart combined — are a testimony to Lady Gaga’s appeal and the hard work of her business team, which devised one of the most extensive and savvy marketing campaigns ever mounted in music.

Once an artist’s biggest source of income, recorded music now plays second fiddle to touring, endorsements, merchandise sales and an array of other revenue streams once considered ancillary. That’s especially true for an artist like Lady Gaga, who has lined up more branding and promotional deals in the last six months than most artists will in a lifetime.