It was a big week in New York last week. More than $1.2bn in Contemporary art was sold representing a rise of 6.7% over the previous year. The Evening sale portion of that total rose at a greater rate than the day sale portion. The Evening sales were up by 7.8% while the day sales total increased by only 2.5%.

That disparity was a product of the very top end of the market. In the Evening sale this May, 46% of the $980m total was comprised by the top ten lots for $461m. Last year, that comparable figure was only 36%. Very strong performances for lots by Jeff Koons, Robert Rauschenberg, Francis Bacon and Mark Rothko were the heart of that story. When very expensive lots get bid upon aggressively, we should conclude that we've seen a shift toward the top of the market. Although the numbers suggest this is more driven by supply—meaning the demand emerged based upon the quality of the lots—than it is by blanket demand or an overall wealth effect. (There's more to say about this when we get to the top Evening sale lots below.)

Curiously, sell through rates were slightly lower this year over last year which may reflect consignors' greater willingness to bear risk or even keep their art even in the face of bidding close to their reserves.