Use mouse scroll to change tool size by 50% only

[einstein]

Hello,

In GIMP preferences I always set my mouse scroll to change brush size relative (by percent).
When I go to:
Preferences > Input Devices > Input Controllers > Mouse Wheel > Main Mouse Wheel > Configure Input Controller > Scroll Up > Select Controller Event Action,
I set it to:
Tool's Size: Increase Relative.

Analogously, I do with Scroll Down, to decrease tool size.

Thing is, it changes the tool size twice, so 100%. I'd love to be able to change my tool's size only by 50%.
Is it possible?