The annual May Impressionist-modern and postwar-contemporary auctions in New York this month made huge numbers, with a new record set for the most expensive artwork ever sold, among quite a few other new high marks. Many works had hit the block before, this time selling for multiples of what they had gone for in the past. Above, a look at the ten works that earned the best annualized rate of return, when comparing their sales price earlier this month to their last auction price, as calculated by Skate’s Art Market Research. (Note that this calculation deducts commissions and does not include taxes and other ownerships costs.) The colored bars indicate the difference in sale price between this month’s sale and its previous auction price. The axis along the bottom indicates the length of time that the work was held between auctions.