Logically, when hiding both found and unfound, all caches will be hidden/excluded. One could argue that it would be a nice idea to be able to do what you want. But I don't think it would be user friendly to do it like this.
The intention behind the chart isn't really to just view your own, though it is possible with below mentioned workaround.
PS! I will move it away from the Bug report category, since we do not consider this a bug, but design.