If Fleetwood Mac's recent record sales are any indication, they can expect to see plenty of enthusiastic crowds during their upcoming tour with the recently returned Christine McVie.

According to Billboard, news of the band's reunion with McVie -- and reports of a possible new album -- have spurred a renewed interest in their back catalog, with a week-to-week 33 percent gain in physical sales and a 52 percent spike in digital song sales.

Unsurprisingly, the focus is on Fleetwood Mac's most popular tunes, with 1988's single-disc 'Greatest Hits' compilation leading album sales and McVie's signature track 'Songbird,' first released in 1975, topping their single downloads. Billboard reports that 'Greatest Hits' has re-entered the Billboard 200 albums chart at No. 200, and risen to No. 32 among its Top Pop Catalog Albums.

Although the fruits of the Mac/McVie reunion won't be heard for some time -- the tour isn't scheduled to start until September, and nothing definite has been announced in terms of new music -- the group's recent round of publicity announcing her return, including an appearance on the March 27 edition of NBC's 'Today' show, was apparently enough to remind people of the Mac gaps in their music libraries. Once they actually hit the road, those numbers should continue to climb.

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