How much less does it cost a top quartile college to deliver a degree than an average college? You can use a cascade chart to show both how much lower the cost is and why the cost is lower. The chart below breaks out cost differences into key components:
The chart is from a McKinsey study entitled, "Winning by Degrees: The Strategies of Highly Productive Educational Institutions." I redid the chart in our Mekko Graphics software. Check out the report for more details on the data and for similar charts and analyses.
I thought this was a great use of a cascade chart. You could use a similar chart to compare costs across divisions or regions within a company. Don't forget to normalize your data (e.g., per employee or per customer) and to identify the key components in a way that brings home your message.