Adele [1]'s "21" album not only returns to No. 1 on the Billboard 200 chart (up two spots), but also becomes the first to sell more than a million copies this year.

With 88,000 sold this past week (down 6%) according to Nielsen SoundScan, "21's" total rises to 1.03 million. The year's second-biggest selling album remains Mumford & Sons [2]' "Sigh No More," which has shifted 645,000.

Adele, Jennifer Lopez Extend Reign on U.K. Charts [3]

Last week's No. 1, Britney Spears [4]' "Femme Fatale," falls to No. 2 with 75,000 (down 73%). The chart's highest new entry comes from rock band Hollywood Undead [5], as its second studio effort, "American Tragedy," bows at No. 4 with 66,000. It's the act's highest rank and sales week yet. The group's first set, "Swan Songs," debuted and peaked at No. 22 in 2008 off a 21,000 start.

Hollywood Undead's album is one of only two new arrivals in the top 10. Asking Alexandria [6]'s new "Reckless & Relentless" also opens at No. 9 with 31,000 -- also its best week ever. The band's first full-length album, 2009's "Stand Up and Scream," spent one week on the list at No. 170 -- though it has gone on to sell 92,000 total.

Next week's chart should look a little more lively, as we expect big bows from Foo Fighters [7]' "Wasting Light," Alison Krauss and Union Station's "Paper Airplane" and Maná [8]'s "Drama y Luz," among others.

Listen to Foo Fighters' 'Wasting Light' Album Here [9]

As for the rest of this week's top 10, Radiohead [10]'s "The King of Limbs" moves up three spots to No. 3 with 67,000 (down just 2%), as sales from a belatedly-shipped deluxe edition of the album reaches consumers. Wiz Khalifa [11]'s "Rolling Papers" slips 2-5 with 59,000 (down 70%), Chris Brown [12]'s "F.A.M.E." shuffles 4-6 with 51,000 (down 44%) and the "Songs For Japan" compilation moves 5-7 with just under 51,000 (down 29%). Mumford & Sons' "Sigh No More" rises 11-8 (34,000, down 7%) and Kirk Franklin [13]'s "Hello Fear" drops one spot to No. 10 (31,000; down 33%).

Over on the Digital Songs chart, Katy Perry [14]'s "E.T." holds at No. 1 for a fifth straight week, selling 323,000 (down 1%) while the Black Eyed Peas [15] are also stationary at No. 2 with "Just Can't Get Enough" (185,000; down 9%). Rihanna [16]'s "S&M" is another non-mover at No. 3 with 141,000 (down 11%). We'll see the impact of the just released remix of the track -- featuring Britney Spears -- on next week's chart.

Britney Spears, Rihanna Team for 'S&M' Remix [17]

The top debut on the Digital Songs tally belongs to Blake Shelton [18] with "Honey Bee" at No. 4 (139,000). The singer co-hosted last week's Academy of Country Music Awards (April 3) with Reba McEntire [19] and premiered the song on the show. It marks the best sales week and highest position for a solo country male artist, surpassing the previous high set when Trace Adkins [20]' "You're Gonna Miss This" jumped to No. 8 on April 4, 2008 with 100,000.

Spears' "Till the World Ends" vaults 15-5 with 133,000 (up 48%) following the track's video premiere last week. Chris Brown's "Look at Me Now" slides down one spot to No. 6 (126,000; down 8%), Jennifer Lopez [21]'s "On the Floor" falls three rungs to No. 7 (125,000; down 9%) and Adele's "Rolling in the Deep" is up one to No. 8 (124,000; up 2%). At No. 9 we find Pitbull [22]'s "Give Me Everything," which flies up 49 spots with 112,000 (up 259%). Closing out the top 10 is Lady Gaga's "Born This Way," which falls two positions with 110,000 (down 14%).

Overall album sales in this past chart week (ending April 10) totaled 5.87 million units, down 11% compared to the sum last week (5.53 million) and up 11% compared to the comparable sales week of 2010 (5.28 million). Year to date album sales stand at 83.70 million, down 4% compared to the same total at this point last year (87.23 million).

Digital track sales this past week totaled 23.18 million downloads, down 6% compared to last week (24.52 million) and up 4% stacked next to the comparable week of 2010 (22.37 million). Year to date track sales are at 362.28 million, up 8% compared to the same total at this point last year (334.75 million).

Next week's Billboard 200 competes with the same week in 2010 when Justin Bieber [23]'s "My World 2.0" held at No. 1 for a third non-consecutive week, selling 92,000 (down 10%). The top debut was MGMT [24]'s "Congratulations," which arrived in the No. 2 slot with 66,000.