Blind Lemon Jefferson, the great blues musician, was once asked why there were so few white bluesmen. He replied, 'Knowin' all the words in the dictionary ain't goonna help if you got nuttin' to say.'
This image, from the graphic design book Diagraphics II, attempts to show the relative market shares of Sotheby's vs. Christies over time. The graphic designer has cleverly used a variety of tricks to show.... What? Well, it does make clear that time is increasing over time. But there surely isn't much else going on.