It's not a rule! It's a law of Physics. What goes up must come down and in stocks it also works the other way around too. You can look at any chart you want to look at and there will be some point where a stock no matter what trend it is in will reverse that trend for a time before the major trend continues once again. Even a major trend will reverse itself, if you follow it long enough. Any major tend can reverse and become the opposite major trend. There are no exceptions to this.
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