I love it when someone turns raw data into a well visualised representation. One I found today is of US energy consumption, below (original here – it’s better to look at that as it doesn’t come out at full width here). This shows data for sources and sinks of energy, clearly differentiates what is used from what is lost, and shows which sources are used in which sinks. A waterfall bar-chart is not as good as it gets!
It’s not a new idea though of course, just underused. The first chart like this was done by Charles Joseph Minard in 1869 to show the Napoleonic campaign in Russia. In some ways that was even more advanced than this since it included geographical information as well. The shocking thing is that the width of the lines represents the numbers of troops, so the difference between the huge brown bar at the start, and the tiny black line at the end is a very starck representation of just how few troops survived. For those who haven’t seen it, the fuill sized image is here, and a small version below :-