There is a known issue regarding the behavior of imported graphics when resizing a page using the Resize Tool. If a page resize is executed with an imported graphic aligned to the page margins, the graphic will not maintain its position relative to the page. Instead, it will remain in the same position it was in pre-resize. 


Graphic position in both pre and post-resize. (100% to 90% reduction)

While this may require an additional adjustment afterwards with the Selection Tool, one workaround to prevent this from occurring altogether is aligning the graphic with the page edge, rather than the page margin.