Is there actually a rule to how expensive a wending ring should be?

Someone told me it had to be x times your salary.

I actually never heard that before. But another person said the same, altough the x was different.

I'm wondering if this common?
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+1 y
Just for the record. I already bought a ring and we decided the budget together.

My girl doesn't even want a too expensive one as she likes wedding rings to be a bit more modest (easier when wearing it daily)

I actually played quite a bit more for the engagement ring.
This question to see if this rule is real of made up
Is there actually a rule to how expensive a wending ring should be?
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