Physical album sales continued to decline and digital album sales grew during the first six months of 2010, according to data released Wednesday by Nielsen SoundScan.

Through the end of June, album sales (physical and digital) were down 11% overall, with 154 million units sold. Physical albums declined 17.7% (112 million sold), while digital albums rose 13.7% (42 million sold). Digital track sales were flat during the first half, with 597 million sold.

CD sales dropped 17.9% during the first six months, with more than 110 million units sold. Current CDs were off 14.7%, while catalog CDs plunged 22.1%. However, the vinyl LP continued to gain, rising 9.1% (1.3 million units sold)

Digital albums now account for 27.4% of all album purchases, up from 21.5% at the same point last year.

Universal Music Group was the market share leader in album sales for the first six months of the year, with 29.41% (vs. 30.7% for the same period last year). Sony Music Entertainment was second with 28.28% (vs. 26.46 in ’09), followed by Warner Music Group with 15.5% (vs. 16.4% in ’09) and EMI Music with 10.79% (vs. 8.84% in ’09). Up nearly 2%, last-place EMI showed the biggest album market share gain.

Nielsen Entertainment senior vp of analytics David Bakula noted, “Strong releases in 2010 have helped to slow the decline of new album sales. Albums by Eminem, Justin Bieber, Lady Antebellum, Lady Gaga and Sade have each sold more than a million copies so far this year, and Lady A’s ‘Need You Now’ has sold more than 2.3 million albums, surpassing last year’s best seller of this time period by a million units.”

On this week’s album chart, Eminem maintains a torrid pace, as his new “Recovery” holds onto the No. 1 slot for a second consecutive week.

Rapper’s Aftermath set drops 58% in its second frame, but hangs at the pinnacle with 313,000 sold, according to Nielsen SoundScan figures for the week ending July 4.

Drake’s “Thank Me Later” (Young Money) also maintains its No. 2 post of last week with 105,000 copies sold (off 33%).

Atlantic’s “Twilight Saga: Eclipse” soundtrack, lofted by the blockbuster vampire pic’s theatrical release last week, makes a big 69% leap and moves up seven positions to No. 3 with a 65,000-unit performance.

R&B singer-producer-songwriter The-Dream moves in at No. 4 with his third album “Love King” (Def Jam), which arrives with a first-week tally of 58,000.

Holding over near the top are the EMI-distributed “Now 34” compilation, hanging at No. 5 with 45,000 sold (down 18%) and teen popster Justin Bieber’s “My World 2.0” (Island), which rises two poles to No. 6 behind a 41,000-unit week (off 4%).

The week’s other top 10 debut comes courtesy of dance-pop duo 3OH!3’s “Streets of Gold” (Photo Finish), which bows at No. 7 with a 41,000-unit stanza; act is currently riding the Ke$ha collaboration “My First Kiss.”

Wrapping the top 10 are surfin’ singer-songwriter Jack Johnson’s “To the Sea” (No. 8, 35,000 units, down 21%), maturing teen thrush Miley Cyrus’ “Can’t Be Tamed” (No. 9, 32,000, down 68%) and Lady Antebellum’s “Need You Now” (No. 10, 30,000, down 7%).

The solo bow of Outkast’s Big Boi is angling for the top debut on next week’s album chart.