The world art auction business has been shrinking. Total sales are down as are total number of lots for sale. “Artprice also lists the top selling artists, by total value of works sold. The front-runner is Picasso, followed by Renoir, Warhol, Degas and Mantegna (in fifth place, up from 12,734th place) a suitably absurd piece of knowledge since there is unlikely to be another Mantegna on the market again, ever.”