Normal distributions follow the empirical rule, also called the 68-95-99.7 rule. The rule tells us that, for a normal distribution, there’s a 68% chance a data point falls within 1 standard deviation of the mean, there’s a 95% chance a data point falls within 2 standard deviations of the mean, and there’s a 99.7% chance a data point falls within 3 standard deviations of the mean.

Read More