How much difference is there in the diameter and section width of a tire on different width rims?

Tirerack says that a GY Wrangler Silent Armor 245/75R16C has a diameter of 30.5 inches and a section width of 9.8 inches when mounted on a 7 inch wide rim. How much, if at all, would those numbers change if mounted on a 8 inch rim?

Any examples wouldn't need to be specifically that size. Just curious.

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2007 KJ Limited 4x4

29G, Tow pkg, full skids, bun warmers, moon roof
Amsoil Air Filter, CB, custom cargo box
OME / Rancho Lift / Rockcrusher rear Diff Cover / Super Skink Sliders (not installed yet)
245/75R16 GY MT/R's with Crager 16 x 8 x 5" BS wheels
L.O.S.T. # 005465

You'd drop to about 30.2",and have a section width of about 10" or slightly more.

Great! So, roughly a 1 % decrease in diameter and a 2% increase in section width.

Thanks. That will come in handy.

_________________
2007 KJ Limited 4x4

29G, Tow pkg, full skids, bun warmers, moon roof
Amsoil Air Filter, CB, custom cargo box
OME / Rancho Lift / Rockcrusher rear Diff Cover / Super Skink Sliders (not installed yet)
245/75R16 GY MT/R's with Crager 16 x 8 x 5" BS wheels
L.O.S.T. # 005465