GCVS remarks A/H ratio. What is it?

Greetings,

I have seen for a few stars in VSX that have an A/H= value that seems to range from -1.0 to +0.2 in the remarks.  I have searched and searched on the GCVS web pages, the literature and I have not found anything that describes what A/H is.

Of course, VSX has copied the remark. 

Anyone got an idea what A and hence H constants are? 

Thanks, (DEY)