If you want the Grid's height to be 100%, then the pager will be 100% to the bottom. If you want the pager under the data, then the Grid's height will not be 100%. How would you expect the pager to move itself if you are telling the grid to render 100% the height of the page? The pager will always appear at the bottom of your Grid, so if your Grid is 100% the height of the page then the Pager will appear at the bottom of the page.
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