Path Properties:Tablet Pen Pressure

is there such a thing?

Theoretically, there must be. in order for a calligraphic brush pen to store the data and appropriately render the actual path the path seemingly MUST contain SOME type of information about how the brush tool was used.

So my question is, is there anybody out that that knows what this property is? or how it's called? any help is appreciated, even if it's just a large repository of adobe properties i could search through.

thanks in advance,