Axes (Aren't Evil)
Axes are so important to the analytical experience that they require some extra attention. If your users do not have a good frame of reference for the view they are looking at, they will be flying blind. Here are some things to consider to make sure your axes line up.
Fixed axes: The axis range automatically adjusts based on the data included in your Tableau view. However, if you are filtering the view, your audience may not notice the axes changing, which could be misleading. You can fix the axis to a specific range of values to avoid confusion.
Axis gridlines: If fixing your axes would be desirable but isn’t practical (this is often the case if you’re dealing with a large range of data), add grid or reference lines to the view. This will signal when the axes are changing.
Axis label: Make sure the axis label is appropriate and includes units when necessary (see our Knowledge Base article for step-by-step instruction).
Axis tick label: Make sure that the values on the axis are formatted appropriately (e.g., currency, unnecessary decimal places, etc.)
Notice the big changes in the axes ranges as you select different metro areas – this would make a poor comparison tool. The author is assuming (probably correctly) that people are concerned primarily with the housing market in their city. It’s a great tool to look at that.