I know that to spike means to rise quickly, and that's also what dictionaries told me. However, when talking about charts and graphs, the noun spike actually includes both the sharp rise as well as steep fall of a metric, hence forming a shape akin to a spike.
Therefore I wonder, does the more general usage of to spike in the sense of rising sharply also imply that the thing being described also quickly falls back down shortly after? Or does it both have and not have this implication, depending on context (aside graphs)?