I'm completely ok with a combined product/licnensing revenue approach to derive the target values Merrit referred to. sorry can't help solve your question, but I am comfortable in relying on Merrits estimates as to where the company is at/heading regarding rates
I doubt they would project a likely decline in future rates and still estimate a higher future $/unit then they are now receiving. Seems pretty straighforward to me, the present rate is a little under $2/unit - per Merrit
Here's the link to the presentation if you care to give a listen, the comments I mentioned were maybe 18 or so minutes in to the presentation