How to read a derived property specification without triggering it to recalculate?

Hello, my model has a derived property specification that I frequently read its value for downstream calculations.  To read this value, I use element.refGetValue("property name").  The issue is refGetValue triggers this property to recalculate each time I read its value thus slow down the routine considerably.  

 

Question: what is the api to read derived property specification without triggering recalculation?

 

Thanks,

Van