I would have sworn I had replied to this a couple of days ago… but then I discovered a half-finished reply moldering offline. Sorry for the delay…
Short answer: No, somehow, you’ll have to make sure each new record added to the table is linked to the summation table. How that happens — and how much pain it imposes — depends on your overall work flow.
From your description, I couldn’t tell if this was a one-off process, an every-now-and-then process, or an after-every-record process. If it is the latter (which seems unlikely), I’d probably name the single record in the calculation table something like ‘’ (the Heavy White Check Mark emoji). Then, during data entry, you would click once on the plus sign in the linked record field and a second time to select the record itself. That’s a two-mouse-click expenditure of effort to create the link, which seems reasonable — and the check mark that appears in the linked record field offers a nice visual confirmation the link has been made.
For less-frequent intervals, you might prefer the cut-and-paste method I described, which has the benefit of being able to modify multiple records at once.
There is also the option of using a third-party middleware offering such as Zapier to perform trigger-based updating of the link field. Personally, that strikes me as overkill, but should you decide to go that route, in the
[Documentation] table of my Wardrobe Manager base there is a PDF attachment entitled “Wardrobe Manager Zapier Guide” that provides step-by-step instructions on setting up a very similar Zapier Zap; only the field to be updated would need to be changed.