Doing Maths in Advanced renamer

What i would like to do is some math in the process, i searched the forum, couldnt find anything.

Is there a way using tags to subtract dates or will i need to use a script?

Example

I can do the replace, change it to days or weeks or months, just wondering how i do the sums.

I would like to use replace rules to find Paul Diddly then replace it with Date taken minus My date of birth

So it would say Paul Diddly (25yrs) or Sarah Diddly (3mnths)

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