Grammys 2012: Photos From The Show and Backstage
The performance many have been waiting for: Adele performs the Song and Record of the Year winner, "Rolling in the Deep."

Not counting albums that were released on an irregular schedule, or, arrived early due to street-date violation sales, Adele's "21" achieves the largest weekly unit gain for an album since Nielsen SoundScan began tracking data in 1991. It earned a staggering 493,000 gain last week -- moving from 237,000 copies last week to 730,000 this week.

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With that 207% increase, it also easily spends a 21st week at No. 1 on the Billboard 200 chart.

Clearly, Adele's performance (and six wins) on the Feb. 12 Grammy Awards spurred "21's" massive sales increase. The annual broadcast can be counted on for generating big bumps in sales, but Adele's is the biggest.

The previous largest SoundScan-era gain for an album came on March 15, 2003, when Norah Jones' "Come Away With Me" jumped from No. 3 to No. 1, selling 621,000 (up from 144,000 the week previous). Coincidentally, Jones' jump was caused by the Grammy Awards, too.

Jones won three of the top Grammy categories that year: album ("Come Away With Me") and record of the year ("Don't Know Why"), in addition to best new artist.

SLIDESHOW: Best of the Grammys

Only three albums have seen a larger unit gain in a week than "21," but all were generated by irregular debuts or off-cycle releases.

-- Eminem's "The Eminem Show" jumped from 285,000 to 1,322,000 on June 8, 2002 in its first full week on the chart -- and second week at No. 1 (a gain of 1,037,000). Its 285,000 debut at No. 1 was engineered by an early release, and, at most, only three days of sales. After its first full week in stores, it then incurred the massive jump in sales.

-- Pearl Jam's "Vitalogy" zoomed from 10,000 to 877,000 on the chart dated Dec. 24, 1994 -- its third week on the chart. The album was released on vinyl LP first (debuting at No. 55 on Dec. 10 with 34,000) before falling to No. 173 with 10,000 the next week. Once the CD was released, it flew to No. 1 with 877,000.

-- The Notorious B.I.G.'s "Life After Death" went from 6,000 to 690,000 in its second week on the chart -- April 12, 1997 (gain of 684,000). However, its bow at No. 176 with 6,000 was owed to early sales, pre-official street date, that forced the title onto the list prematurely. The next week, after its first official week in release, it jumped to No. 1.