Mail rule does not work

My computer is a Mac mini with Mojave. 

Further to the above, in Mail/Rules, there is the condition that I have tried to use, but have run into trouble with, namely ‘Date received’ — ‘is greater than’ - ‘X days old’. Is there a limit to the value of ‘X’? Does it have to be a single-digit number?

In order to move emails more than a year old out of my inbox and into a specified mailbox ‘on my Mac’, I set X to 365. The result was that almost all my emails were deleted, and nothing was moved to the designated inbox on my Mac. I should be very grateful for further advice.

Thank you very much. Yes, I was expecting it to run automatically. So how do I run it manually?

Thank you again, BobTheFisherman. That, I am sure, has now solved my problem.