Here is an example of deceptive axes. The top graph was one which was originally presented. You can see that the vertical axis does not begin until 28%. This creates the illusion that the tax rate for the rich as decreased dramatically in the past few years. The bottom graph is the same data plotted with a full vertical axis. You can see the difference its makes. Now which one would you want to show if you were lobbying for an increased tax rate for the rich?

http://peltiertech.com/WordPress/tax-the-rich-or-deceptive-axis-scales/