File talk:Bubble diagram showing the share of global cumulative energy-related carbon dioxide emissions for major emitters between 1890-2007.svg

What is the basis of the placement of these bubbles? If a nontraditional graphic is to be used, there should be some sense (intuitively meaningful or explicitly stated) to its appearance. I don't see either in this graphic. If it is geographic, then Russia is out of place. 211.225.39.71 (talk) 01:20, 22 June 2013 (UTC)