Thanks MatPed! So far it seems your English & understanding are better than mine!

I think what you've said helps. But please let me clarify to be sure:

First, strategy expiration is not a part of this, unless I'm missing something like an unstated assumption. I'm assuming whatever strategy we're talking about is still good; otherwise the expiration more than likely overrides everything else.

Then, using your example of a flat account so that the square root rule is not a part of this: The account started at the beginning of year 1 with a certain risk of severe drawdown. To be explicit, x% chance of a drawdown triggering Margin Call.

There seems to be 2 parts to this: "risk" and "severe".

"risk": At the end of year 5 my risk is now (x+y)%. I suspect from what you've written that there's nothing I can do about this - this risk grows continuously as long as I keep trading - right? Is there some other formula/rule that describes this risk growth?

"severe": I also suspect that "severe" has in reality increased also, right? In other words, not only is there a larger % risk of an event; there's also larger risk that the event will be bigger & cause Margin Call even if I've added funds to the account?

To get to the bottom line of all this: What do I need to do (add how much more funds to the account?) at the beginning of year 6 so that I maintain the same x% risk of a drawdown big enough to trigger Margin Call?

Thanks.