Now, if we're talking about two standard deviations around the mean, so if we go down another standard deviation, so we go down another standard deviation in that direction and another standard deviation above the mean, and we were to ask ourselves, what's the probability of finding something within those two or within that range, then it's, you could guess it, 95%. And that includes this middle area right here. So the 68% is a subset of that 95%. And I think you know where this is going. If we go three standard deviations below the mean and above the mean, the empirical rule, or the 68, 95, 99.7 rule tells us that there is a 99.7% chance of finding a result in a normal distribution that is within three standard deviations of the mean. So above three standard deviations below the mean and below three standard deviations above the mean. That's what the empirical rule tells us.