Quoting directly from the developer documentation, which can be found in the / Distribution documentation folder:
4.6.48. Sheet from right to left
Worksheets can be set individually, whether column "A" should start on the left or on the right. By default remains. Here's how to set columns from right to left.
// right-to-left worksheet $objPHPExcel->getActiveSheet() ->setRightToLeft(true);
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