Check deduplication ratio

Is there a functionality which can give me a kind of ratio for the deduplication of all files in a specific storage?

I have backups of many Linux machines in one storage and it would be a nice feature to see e.g. 10% space gets saved because of deduplication.

If you run duplicacy check -tabular and look at those unique chunk numbers, they should give you an idea of how much the deduplication ratio is.