Katya Kazakina does a little math on the Fall 2011 New York sales and finds rising estimates and more guarantees:

The estimates are more aggressive across the board than a year ago, according to Sergey Skaterschikov, founder of Skate’s Art Market Research. The low estimates are up 17.6 percent; the high estimates are up 15.9 percent from November 2010.

To win major consignments the auction houses have increased their guarantees to sellers. Christie’s guaranteed 16 lots in its contemporary art sale, up from 7 a year ago; 10 of them have been backed by third parties. At Sotheby’s contemporary sale there are 10 guaranteed lots, up from 3 last year. All have been financed by third parties.

For these lots, “satisfactory results are baked into the sales,” said Beverly Schreiber Jacoby, art valuation expert. “But whether things fly, that’s where we see if the market is hungry enough.”

Kluge, Wasserman Trophies Test Art Market in $1.1 Billion Sales (Bloomberg)