The Empirical Rule, also known as the 68-95-99.7 rule, is a powerful shortcut for understanding normal distributions. This rule tells us that for any normal distribution:
of data falls within ±1σ of the mean
of data falls within ±2σ of the mean
of data falls within ±3σ of the mean
This rule is essential for quick probability estimates and understanding data spread in normal distributions. The interactive visualization below shows how these percentages remain constant regardless of the specific mean and standard deviation values.