Currency Exchange - Formula is allowed - Enhancement Suggestion

Hi.

It would be nice to be able to use formulas in the Alva's Currency Exchange. A simple "*" would be enough and the simplest the implement.
Example : you choose two items, it gives you the current rate and you type in *7 on each side and press enter to update, placing a single beefier order very easily without using a calculator.



Can be presented like in Helmod https://www.youtube.com/watch?v=9VNa1gEENSw&t=760s.

We already have Regex for stash, formula for the Currency Exchange only could be a sweet addition.