I have a financial desktop application and there are many places where different computations are performed and a single number (or a couple numbers) is shown as a result.
Very often users are asking questions like "how did the system calculate this number" and I would like to give them some UI which that could use to figure it out themselves.
The calculations are not complex (mostly arithmetic and some standard functions one could find in Excel) but there are often multiple stages producing intermediate results and data is taken from different parts of the system. Most of the times the users are confused is because they forget about some (optional) inputs or because it is too time consuming for them to trace intermediate results.
What are some good ideas for a UI that would provide more details about such computations?
E.g. I once saw a team that were building a component to display "expression trees" (operation has inputs as its children and they can themselves be results of other operations and so on).