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Standard Deviation with Asset Prices?
Almost every online datasources provide historical prices on given company / index's performance; from this, you can easily calculate "standard deviation" by yourself. With that said, standard deviation presumes a fixed set of data. Most public corporations have data spanning multiple decades, during which a number of things have changed: For these reasons, I have doubts on simplistic measures, such as "standard deviation" measuring any reality on the underlying vehicle. Professional investors usually tend to more time-point data, such as P/E ratio.