How to make label position centered vertically on the bar?

[toxaus]

Hi!
Could you please help me to make it work?

How can I set the position of the data label inside of a bar always in the middle?
Is there an option to set the minimal height of a single column on the chart to be able to show labels for small values(like 5k, 1k on the image)?
As I understood I should use "onrendered"?

[toxaus]

I found an option " centered: true" it's exactly what I need. But there is a problem when values are too small and there is no space by height to show the label correctly