(Bloomberg News) As the European debt crisis roiled financial markets in 2011, the value of the most expensive works of art sold at auction fell 41 percent.

The priciest 10 lots amounted to $413.6 million, compared with a tally of $698.6 million in 2010, according to Bloomberg News calculations.

With a dearth of major estates and masterpieces by market stars, not a single artwork crossed the $100 million threshold in 2011, compared to two pieces the previous year: Pablo Picasso's 1932 painting "Nude, Green Leaves and Bust," which fetched $106.5 million at Christie International, and Alberto Giacometti's bronze "Walking Man," which sold for 65 million pounds (then $103.4 million) at Sotheby's.

Evening sales of Impressionist and modern art in London and New York dropped by 21 percent from last year; their postwar and contemporary counterparts fared better, gaining 35 percent, according to Bloomberg News calculations. Together, the major auctions, including private collections, in these categories at Sotheby's and Christie's International tallied $3 billion, just beating the $2.9 billion in 2010.

Museum-quality works by undervalued artists, from Old Masters to postwar set records and ignited bidding wars.

Here are the year's 10 most valuable artworks at auction.

1. A large abstract painting by Clyfford Still fetched a record $61.7 million at Sotheby's on Nov. 9, surpassing the reclusive artist's previous auction high of $21.3 million. The brooding canvas, "1949-A-No.1," led a group of four Still lots consigned by the City of Denver to raise money for the endowment of the Clyfford Still Museum, which opened in November. The group tallied $114.1 million.

2. Roy Lichtenstein's 1961 painting of a man looking through a peephole sold for $43.2 million at Christie's International on Nov. 8, setting a record for the pop artist. Titled "I Can See the Whole Room!... And There's Nobody in It!" it was consigned by Courtney Ross, the widow of former Time Warner Chief Executive Officer Steven J. Ross.

3. An 18th-century view of Venice's Grand Canal by Francesco Guardi fetched 26.7 million pounds ($42.7 million) at Sotheby's on July 6, a record for the artist and the second-highest price paid at auction for an Old Master painting. Dating from the late 1760s, the work was consigned by heirs of the Conservative politician Paul Channon, who died in 2007. The record auction price for an Old Master is 49.5 million pounds for Peter Paul Rubens's "Massacre of the Innocents" at Sotheby's London in 2002.

4. Pablo Picasso's painting of his mistress Marie-Therese Walter sold for 25.2 million pounds ($40.5 million) at Sotheby's on Feb. 8. Painted in 1932 -- the same year as Picasso's Walter- inspired "Nude, Green Leaves and Bust" -- "La Lecture" attracted seven bidders and was bought by a client of Mark Poltimore, deputy chairman of Sotheby's Europe, who works with Russian buyers.

5. A 1915 landscape by Gustav Klimt surged past its presale estimate of $25 million to reach $40.4 million at Sotheby's on Nov. 2. Stolen by the Nazis from its Jewish owner, the work was consigned by the woman's grandson, Georges Jorisch. "Litzlberg am Attersee" depicts verdant hills above the lake of the title in western Austria. Earlier in the year, Museum of Modern Art in Salzburg, Austria, returned the painting to Jorisch. Zurich dealer David Lachenmann bought the work on behalf of a client who he declined to identify.

6. A 1914 townscape by Egon Schiele fetched an artist record 24.7 million pounds ($40 million) at Sotheby's on June 22. Titled "Houses with Laundry (Suburb II)," the work was offered by the Leopold Museum in Vienna to pay for its "Portrait of Wally," Schiele's 1912 portrait of his lover Walburga (Wally) Neuzil at the heart of the world's longest- running art-restitution case. Sotheby's Poltimore bought the work for a client.

7. Andy Warhol's 1963-64 "Self-Portrait," made of four photo-booth-strip images in different shades of blue, sold for $38.4 million at Christie's on May 11.

8. Francis Bacon's 1964 painting "Three Studies for a Portrait of Lucian Freud" fetched 23 million pounds ($37 million) at Sotheby's on Feb. 10. The artist sitter, grandson of Sigmund Freud, died in July. The triptych was the star of a 60- lot sale of works that had belonged to the low-key Geneva collector George Kostalitz. The group raised 93.5 million pounds.

9. A 1765 painting of a champion race horse by George Stubbs brought an artist record 22.4 million pounds ($36 million) at Christie's on July 5. Titled "Gimcrack on Newmarket Heath, with a Trainer, a Stable-Lad, and a Jockey," the canvas depicted a horse that had won 27 of the 36 races he entered. It was consigned by the U.K.-based Woolavington Collection and was bought with a single bid by Piers Davies Fine Art of New York.

10. An undocumented Mark Rothko canvas, "Untitled No. 17," fetched $33.7 million at Christie's on May 11, surpassing its high estimate of $22 million. Painted in 1961, it depicted pink and red rectangles on a tangerine-yellow background and hadn't been seen publically since 1965.