May 19, 2014
Makeover Monday: India's BSE Sensex as an Area Chart
I'm not a huge fan of area charts, especially stacked area charts. Much like bar charts, the axis for an area chart needs to start at zero, otherwise you're not showing the total area, thus defeating the purpose of using an area chart in the first place.
As an example, here's a recent chart from Chart of the Day about India's stock market.
Notice how they've started the axis at 2,600. This distorts the slope of the graph and also the area of the graph is not complete.
Contrast this to Yahoo!'s chart, which is executed perfectly.
Yahoo! is showing the entire scale and nice proportions. Without noticing these subtle differences, you might interpret a very different story. Moral of the story: always start the axis for area charts at zero.