Could you please clarify what exactly is meant by the "90% rule" in trading? I've heard it mentioned in several financial discussions, but I'm not quite sure how it applies or what its significance is. Is it related to risk management? Or does it have something to do with the allocation of trading funds? Could you elaborate on the concept and provide some examples to help me understand it better? Additionally, are there any specific conditions or trading strategies that this rule is particularly applicable to? Thank you for your assistance in clarifying this matter.