The music-buying public continued to curb its spending on albums last year, but sales of digital singles skyrocketed as consumers continued to embrace the online availability of music a la carte.

According to year-end sales figures released Thursday (1/4) by Nielsen SoundScan, US consumers bought 588.2 million albums in 2006, down 4.9 percent from 2005. Offsetting the continued bleeding (2005 album sales were off 7 percent from 2004) is the sale of digital tracks, which jumped from 352.7 million in '05 to 581.9 million last year. The surge helped overall music sales clock in at about 1.2 billion units, a 19.4 percent increase over '05. The '06 total marks the second consecutive year--and only the second time ever--that unit sales have crested the 1 billion threshold.

The crown for top-selling album of '06 goes to Disney's "High School Musical [ tickets ]" soundtrack, which racked up sales of about 3.7 million copies. Lining up behind that album are Rascal Flatts [ tickets ]' "Me and My Gang" at No. 2 with sales of about 3.5 million copies; Carrie Underwood [ tickets ]'s "Some Hearts" with 3 million; Nickelback [ tickets ]'s "All the Right Reasons" with 2.7 million; Justin Timberlake's "Futuresex/Lovesounds" with 2.4 million; James Blunt [ tickets ]'s "Back to Bedlam" at 2.1 million; Beyonce's "B'day" with 2 million; the "Hannah Montana" soundtrack with 1.99 million; Dixie Chicks' "Taking the Long Way" with 1.86 million; and Hinder's "Extreme Behavior" with 1.8 million.

In addition to scoring the No. 2 top-selling album of '06, Rascal Flatts also earned the distinction of top-selling artist, with cumulative sales of about 5 million copies for the year. Johnny Cash followed, with fans buying about 4.8 million albums from his catalog, sales of which were presumably fueled in part by the success of the late-2005 Cash biopic "Walk the Line." Falling in behind the two sales leaders are Nickelback, Carrie Underwood, The Beatles, Tim McGraw, Andrea Bocelli, Mary J. Blige, Keith Urban and Justin Timberlake.

Topping the list of 2006's best-selling digital tracks is Daniel Powter's "Bad Day" with about 1.9 million units sold, followed by Gnarls Barkley's "Crazy" with 1.6 million; The Fray's "Over My Head" with 1.51 million; Sean Paul's "Temperature" with 1.5 million; Hinder's "Lips of an Angel" with 1.37 million; Shakira's "Hips Don't Lie" with 1.36 million, barely edging out The Fray's "How to Save a Life" by a mere 400 copies; Natasha Bedingfield's "Unwritten" with 1.35 million copies; Justin Timberlake's "Sexyback" with 1.31 million; and The Red Hot Chili Peppers' "Dani California" with 1.28 million.

Continued brisk holiday sales of Apple's iPod line, as well as other digital-music players and computers, seems to have translated into a post-Christmas surge in digital-track sales, which hit a record one-week high of 30.1 million during the final week of 2006. That buries the previous record of 19.9 million set during the final week of 2005.

As further proof of consumers' transition to digital music, 22 digital songs exceeded the 1 million sales mark during 2006, compared to only two songs in 2005.