LWJGL camera zooming?

So I have a float value called zoom. Zoom can be anywhere between 0.0125 and 1, with 1 being fully zoomed out, and 0.0125 being approximately 80 times zoomed in.

I’m attempting to change this value using the mouse scroll wheel, but I’m not sure how I would want to get a smooth zoom. Would I repeatedly add (0.0125 * scroll wheel change) to the zoom value?

Or would I perhaps multiply zoom by something like 1.05?

Essentially, the question is, how would I go about creating a smooth zooming “range”?