So that's from the first sample, the contribution from the first sample. And then from the second sample, you have this guy over here, 5, oh sorry, you don't want to calculate him. For this data point, the amount of variation due to the difference between the means is going to be 4 minus 4. It's going to be 4 minus 4 squared. Same thing for this guy. It's going to be 4 minus 4 squared. We're not taking it into consideration.