And notice, for every data point I had before, I now have five more than that. So this is my new data set, which I'm calling data plus five. And let's see what the mean of that is. So the mean of that, notice, is exactly five more. And the same would have been true if I added or subtracted any number. The mean would change by the amount that I add or subtract. And so, and that shouldn't surprise you, because when you're calculating the mean, you're adding all the numbers up and you're dividing by the numbers you have.