Changing font in "graph summary labels"

Hi

I am using ICADVM20.1-64b.500.28.

I would like to ask, if there is any command or way how to change the font size in graph summary label. Look at the image. I have a lot of histograms and I need "mean" "number" and "std dev" items to be showed. So I have to open every graph properties and manually change font from 10 to 8, is it possible to do it automatically?

Thanks

Roman