This is a bad visualization because it is hinting at a visual congruence that isn't there. When plotting things with two Y axes, you have to be really careful

This is a bad visualization because it is hinting at a visual congruence that isn't there. When plotting things with two Y axes, you have to be really careful and honest about what you're trying to look at. When you use a line graph, visually, you're displaying a trend (in the most naive way possible). When you have two Y axes, then you need to ask, "What is a valid way to compare two trends?" Remember, a trend is intrinsically about slope. If you arbitrarily adjust the min/max axis value, then you can arbitrarily adjust the appearance of the trend. Here is a fixed version that shows the actual numbers on full, 0-based scales: http://i.imgur.com/xiS2OZq.png http://i.imgur.com/xiS2OZq.png Hopefully this shows you how deceitful Thiel's plot is, even though the axes are "clearly labelled". Iconic perception trumps reading numbers. Here is a year-over-year plot: http://i.imgur.com/diDVNeE.png http://i.imgur.com/diDVNeE.png An alternative, more meaningful visualization, would be to show % change from a baseline, in this case the 2003 value. That would be far more honest and informative. And here it is, as a bar plot, which is more effective for comparing values along a common scale. (Since we have computed percent change, we have a common scale.) http://i.imgur.com/TQd2u22.png http://i.imgur.com/TQd2u22.png *Note: I just read the numbers off of Thiel's plot and don't have the source data, so this plots are approximations. I can share a simple IPython notebook of this if anyone really cares.