Instead of directly modifying your database object, I would recommend making a business logic layer for binding. Tools like https://github.com/AutoMapper/AutoMapper make it easy to transfer most of your table entities across without modification and then do things like create summary values, complex computed fields and other non-stored data tasks.
In MVC this is called Model, View, ViewModel, Controller, where the ViewModel is what you bind to and has all the computed results.
This does introduce additional complexity, but it leaves your Model objects alone (which is a good thing) and allows you to isolate your rules to one location (the ViewModel) which can avoid spreading the same computations across many controllers (which is an anti-pattern).