Let's say I'm trying to judge how many years of experience we have at the Khan Academy, or on average, how many years of experience we have. And in particular, the particular type of average we'll focus on is the arithmetic mean. So I go and I survey the folks there. And let's say this was when Khan Academy was a smaller organization, when there were only five people in the organization. And I find, and I'm surveying the entire population, so years of experience, the entire population of Khan Academy, because that's what I care about, years of experience at our organization, at Khan Academy. This is when we had five people. And I were to go, we're now 36 people.