I found the following set of bar graphs at www.mrexcel.com in an article that explored the new features of Excel 2007. Mr. Excel credits http://blogs.msdn.com/excel/ as the original source of these images.
These charts were created to show the superiority of Excel 2007’s new charting engine (bottom) compared to earlier versions of Excel (top). I agree that the top chart needs improvement: its design distracts from the data and is just plain ugly. My comments, however, will focus on the so-called “superior solution.”
If you wanted to hang some abstract art on your wall, the bottom graph would serve nicely. As a work of art, it is the more attractive of the two. It’s when it comes time to actually decipher the data that the problems begin.
Although it is presented as cutting edge of technology, the bottom chart uses a black background with white text, a relic from the early years of computers. In the past, the use of white or other light text on black emerged from necessity; early monitors and projectors simply weren’t bright enough to clearly display black text on a white background without annoying flicker. As such, white text on a black background was used as a compromise, which is no longer necessary. Most modern graphs should use a white or off-white background to allow the information itself (points, lines, bars, etc.) to stand out clearly in contrast.
Here are a few of this graph’s problems:
Here’s my redesign:
Line graphs make it especially easy to see the patterns of change and to focus on trends. To avoid the clutter of seven lines on a single graph, I used “small multiples,” a series of seven small graphs, which vary by region, but otherwise look and work the same. Small multiples may be arranged vertically (shown above), horizontally, or in a matrix. Because this information is a projection (and so the exact magnitudes are probably not as important), I have made the assumption that the graphs should be arranged to make it easiest to compare the patterns of change for the various regions, which is why I aligned the years by arranging the graphs vertically. If the magnitudes of the lines were more important, then a horizontal layout would have been preferable, for easier magnitude comparisons. Notice that the horizontal label (showing the years) is only shown on the very bottom of the graph. This is all that’s necessary to show which part of each line belongs to which year. Duplicating these labels for each graph would have resulted in redundancy and clutter.
I have reordered the continents based on the 2006 values, with the highest at the top and the lowest at the bottom. I based the sequence on the 2006 value because, as these values are projections, the first year is likely to be most reliable and of greatest interest to decision-makers.
This new design is clean and clear—free of the visual distractions in the first two examples. Anyone viewing the graph would be able to examine the data, focusing perhaps on the large declines that are projected to occur in Europe and Africa, instead of the pretty, shiny bars.