04-05-2016 05:16 AM - edited 04-05-2016 05:16 AM
Unfortunately this is not possible. You can only add the data label for the total value, above the bar chart.
The suggestion to have data labels inside the stacked bar has already been added on this community, you can vote for it here:
I would certainly use this feature a lot if this was available, it makes the stacked bar a lot more powerful.