Page History

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1. add a page to your wiki using the Add menu
2. save the page
3. add an attachment to that page via the Add menu
4. click the Insert/Edit Macro icon in the toolbar 
5. You'll see a dialog box come up. Select the spreadsheet you attached from the File Name popup menu
6. Optionally, if you'd like to show a specific worksheet or row/column range, specify those values in the provided fields
7. Click Insert and then save your page

The macro editor will write the wiki markup for you which will look something like:

{viewxls:name=sample.xlsx|sheet=Summary|row=13|col=3}

Example of an Embedded Spreadsheet