For example, Morningstar displays the S&P 500 standard deviation in three, five, and 10-year measurements. The empirical rule describes how the points in a data set are clustered around the center.

Pawelczyk, Martin, Chirag Agarwal, Shalmali Joshi, Sohini Upadhyay, and Himabindu Lakkaraju. "Exploring Counterfactual Explanations Through the Lens of Adversarial Examples: A Theoretical and ...