Out of the box you cannot do it.
You have to get a separate plugin in the marketplace. Search the forums and you will get lots of hits for recommendations. Example: https://community.atlassian.com/t5/Confluence-questions/Is-it-possible-to-perform-sum-calculation-in-a-confluence-table/qaq-p/872029
Hi Atlassian Community, My name is DJ Chung, and I’m a Product Manager on the Confluence Cloud team. Today, I’m excited to share a new and improved version of Home. The new Home helps you ...
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