Unfortunately, I don't think anyone can tell you, not even your doctor, though his/her guess will be worlds better than anyone on this message board. (I'm assuming you meant "without" rupture or intervention.)

There is data out there on risk of dissection/rupture versus aneurysm diameter. Your doctor should be able to give you that population-level data, FWIW. Medicine doesn't have a way to predict that for any individual yet. WRT growth rate, I believe that is non-linear and equally hard to predict. Scaled for your height, I'd guess some doctors might consider a repair now. Some doctors wait for 5.5cm. There is also population level data on growth rates.

So your doctor can give you real data on your odds. Whether they would stick their neck out and try to make a guess based on their experience probably depends on the doctor. It's a conversation worth having.

Having lived with an aneurysm and high CAC for a few years now, one question I'd ask myself is how would the answer change what I do?

I hope it goes well for you.