And I know I'm mispronouncing it. Maybe it's con-cavity. But thinking about concavity, we can start to look at the second derivative rather than seeing just this transition to think about whether this is a minimum or a maximum point. So let's think about what's happening in this first region, this part of the curve up here where it looks like a arc, where it's opening downward, where it looks like an A without the cross beam or an upside down U. And then we'll think about what's happening in this upward opening U part of the curve. So over this first interval right over here, if we start over here, the slope is very positive. Slope is very positive.