LOS ANGELES (Billboard) – Lady Gaga led the U.S. pop album chart for a second week on Wednesday, but inevitably suffered a mammoth sales drop since her opening round was boosted by Amazon.com's 99 cent promotion.

"Born The Way" sold 174,000 copies during the week ended June 5, according to Nielsen SoundScan -- off 84 percent from her spectacular first-week tally of 1.1 million copies. Late last week, prognosticators had forecast a second round of about 200,000 copies.

The album's first week tally -- the biggest in six years -- was unusually bolstered by likely hundreds of thousands of sales generated by AmazonMP3's decision to sell the digital version of the set for 99 cents on two separate days.

At any rate, it's not unusual for big albums to suffer second-week slides. Last week's No. 2 entry, Brad Paisley's "This Is Country Music" saw sales fall 65 percent to 53,000 as the album fell four places to No. 6.

Given Gaga's decline, Adele's "21" will likely reclaim its throne next week for a 10th nonconsecutive week. The English pop singer rebounded one place to No. 2 with 121,000 units -- down just 4%.

Adele's set has yet to leave the top three positions of the chart since its debut 15 weeks ago. It's still too early to tell how either Adele or Gaga will sell this week.

The top debut belonged to Death Cab for Cutie's "Codes and Keys," which started at No. 3 with 102,000. It's the follow-up to the band's No. 1 2008 album "Narrow Stairs," which sold 144,000 upon its debut.

Pearl Jam's Eddie Vedder arrived at No. 4 after selling 71,000 copies of his bare-bones "Ukulele Songs" solo outing. He previously charted on his own with the "Into the Wild" soundtrack, which debuted and peaked at No. 11 in 2007 with a 39,000 start.

Rock band My Morning Jacket's "Circuital" bowed at No. 5 with 55,000. It's the best sales week and highest-charting set for the group, whose previous high-water mark came with the bow of "Evil Urges" at No. 9 with 49,000 three years ago.

The final debut in the top 10 came courtesy of Flogging Molly's "Speed of Darkness," launching at No. 9 with 25,000. Its last studio release, 2008's "Float," debuted and peaked at No. 4 with 48,000.

As for the rest of the top 10, "Now 38" slipped one to No. 7 (39,000), Jason Aldean's "My Kinda Party" rose one to No. 8 (33,000) and "Glee, the Music: Season Two, Volume Six" dropped six to No. 10 (25,000).

Overall album sales totaled 5.5 million units, down 17% from the previous week and up 7% compared with the comparable sales week of 2010 (5.2 million). Year-to-date album sales stand at 131.4 million, up 1% compared with the same total at this point last year.

Next week's top debuts will come from Tech N9ne's "All 6's & 7's," All Time Low's "Dirty Work" and country veteran Ronnie Dunn's self-titled solo debut. Industry sources suggest the former two might sell around 50,000 copies by week's end on June 12, while Dunn could shift 45,000 or so.

Other albums looking for a possible top 20 entry are Arctic Monkeys' "Suck It And See" and Def Leppard's "Mirrorball."