Here’s the result of an Excel add-in developed by
Graphician.com by which the user can apply the company’s proprietary algorithm to adjust any dual-vertical-axis chart created by Excel 2010 (or later) with a single click. The purpose of the adjustment, as described in the preceding post on this topic, is to scale the plots proportionally to promote more accurate visual comparisons.
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| Examples on the left show how the Graphician add-in for Excel scales Y-axes proportionally to promote more accurate visual comparisons between the plots. |
For more information, including a sample Excel file you can use to test the algorithm, go to www.graphician.com.
Perils and pitfalls of dual-axis displays are covered in
Chapter 11: Viewports and Dashboard Displays of
How to Lie with Charts - Investor's (Third) Edition.
