Width and Height get 10 times longer when specified in Animate

Hello

I would like to make an image appear to shrink and widen. When I specify the Width or Height in the Properties window and click the diamond to add a keyframe,

the value I entered gets automatically 10 times longer in the Timeline panel (e.g. 300px to 3000px).

Could someone please tell me how to debug the automultiplication of a width/height?

Thank you in advance,

Ead