If you just need to see a running total, you’ll want to use the summary bar (which does more than just sum) at the bottom of the page of views.
If you want to keep a running total in the record itself, it’s a different story. This post and the accompanying base explains how, but there is an additional step you’ll have to take, either manually or through something like Zapier, to avoid Airtable’s prohibitions against circular logic.
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