Normally one has to turn to scientific literature for really terrible graphics, or USA Today. However, this morning’s Bloomberg Businessweek had a strong contender:
The x-axis is time, though kind of a pointless time, as what’s really being shown is the market’s reaction to six distinct Amazon product announcements. The Y-axis shows peak intraday drop in market cap (with the direction reversed — the more a stock fell, the higher its dot appears on the graph). The size of the dot shows the total loss of market value in dollar terms (so, not adjusted for the size of the company before the drop started). And the sizes are not a simple function of the total drop in value, but instead shows which of three categories a stock’s drop fell into. They’re labelled $100MM (or less, I presume), $500MM (everything between $100MM and $1B, I presume), or $1B (or more, I presume). Since the size of the dot is set at the end of the day, and location on the y axis is set intraday, these elements do not sync and are in some ways not comparable. The color of the dot indicates the industry in which each company operates and we are also given the name of each company.
What conclusion are we supposed to draw from this mess? The only trend I can see is that Amazon seems to be taking on bigger companies. Surely there would have been a more parsimonious, less absurd way of making that point.