And you see that. We increased by one hour here, we increased by 15% on the test. Now, what that means is that the trend it shows is that in general along this trend, if someone studies an extra hour, then if we're going with that trend, then hey, you know, it seems reasonable that they might expect to see a 15% gain on their test. Now let's see which of these are consistent. In general, students who didn't study at all got scores of about 15 on the test. Well, let's see, this is neither true, we don't see that these are the people who didn't study at all and they didn't get 15 on the test, and that's definitely not what this 15 implies. This doesn't say what the people who didn't study at all get.