XOM is one of the stocks that I regularly follow. I have seen its ups and downs. I don't quite understand all the factors that affect its price. One of the things that intrigues me is the crude oil prices - which I also follow.

Question: If I don't consider other factors (such as the broad market conditions): if the crude oil price goes up, will XOM follow and goes up? Converselyly if crude oil price goes down, will XOM drop?

Why when crude oil came down from a peak of $140 a barrel to $40-$50, XOM still stand so tall? It only drop from $90 to now $80.