How to Use Shared Header and Footer RDL Files in Reports

We have a collection of reports all with the same header and footer content. How can we define the header and footer content once and then include it into several reports rather than duplicating the header and footer content in each separate RDL file?

We can do this with RDL running on stand-alone SSRS, but don't see how to do this with the Dyanmics CRM reporting entities.