qgis - Is it possible to label bar charts?

I have added bar charts to my map and this works fine. But I have no idea how to add values to the bar chart. For example one bar shows the value of 2000 and another shows the value of 2100. Is it possible to show this values in the bar chart? I tried labeling but this is not what I want.

Any ideas? A Plugin or something else?

qgis 2.01 and 1.8

Thanks.