Data Input History

[Jeff Honken]

I've been trying to figure out how to destroy the data I've input into a
field after I close the stack.  I'm closing the stack using:

set the destroyStack of this stack to true
  close stack "ProvWiz"

When I open the stack back up the data that I've input is still there. 
How do I destroy the data in the fields when I close the stack?