Displaying hover data for a specific bar when doing a stacked bar chart


I’ve been used the high-level Bar chart option as it makes stacking of bars pretty easy.

I have been trying to get access to the data for individual parts of a bar, but I haven’t found a way to do it. In attached image, I can get the total bar height when I mouse over a bar (61 in this case), but I can’t get the hover tool to display 40 for the size of the orange bar.

Does anyone know if there is a way to do this?

Does the chart raise some sort of event when you mouse over a new part of a bar?