Billboard announced today that starting later this month, its flagship Billboard 200 chart will reflect comprehensive sales of all albums, old and new. How come?

To understand the changed rules, think back to the awkward chart situation that followed Michael Jackson’s death this past summer. Sales of his work immediately skyrocketed, and for six non-consecutive weeks, his greatest-hits set Number Ones was the best-selling album in the U.S. Yet since it was more than 18 months old, Number Ones‘ sales weren’t counted for the Billboard 200. It was instead relegated to lesser-seen charts like Top Comprehensive Albums and Top Pop Catalog Albums, while lower-selling new releases like Sugarland’s Live on the Inside topped the the Billboard 200. A similar fate befell the Beatles’ reissued albums, several of which would have qualified for Top 10 spots on the Billboard 200 this fall if they weren’t so old.

Prior to Jackson’s death, no catalog album had outsold the Billboard 200’s No. 1 in the publication’s history. So this is just a matter of keeping up with the times. “What we’ve seen in the past couple years — and not just with Michael Jackson — is a lot of albums reissued with new content,” Billboard director of charts Silvio Pietroluongo tells the Music Mix, citing successful reissue campaigns for Pearl Jam’s Ten and Jackson’s Thriller. “I think what we’ll see in the future is more labels trying to mine their catalog in creative ways. The Billboard 200 needs to show the sales activity of those titles, and also any older titles that receive a spike due to any other exposure, [such as] an artist appearing on American Idol.”

The change will go into effect with the Billboard 200 dated Dec. 5 (covering the sales week from Nov. 16-22).

What do you think of Billboard‘s new rules? Are you looking forward to seeing older releases competing alongside new ones? Sound off in the comments section.

(Follow the Music Mix on Twitter: @EWMusicMix.)

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