This is a setting that you can change in Excel. 

  • Use Ctrl +A (Cmd + A on Mac) to highlight the whole range and then click the Unmerge cells button/link.
  • If you can't find the "unmerge cells" button you can go to View/Toolbars/Customize and then search for it on the "Commands" tab under the "Format" category.
  • This page at has some tips: Merge and unmerge cells 

Updated 7/13/16