We have to look all the way up into the second to last column, and we have to add a digit of 8 here. This is 2.58 standard deviations. We have 2.5 over here, and then we get the next digit, 8, from the column. 2.58 standard deviations above and below the standard deviation encompasses a little over 99% of the total probability. There's a little over 99% chance that any sample mean that I select from the sampling distribution of the sample mean will fall within this much of the standard deviation. Let me put it this way. There is a 99.2% chance.