How to avoid shape data reset in Visio?

Question

the issue I have is the following. I have defined a Shape Data Set, which includes a list (fixed or variable, doesn't matter). I apply this Data Set to my stencils and begin to create a drawing, choosing an option from the respective list for all the shapes I add. Once in a while I may need to add a new item in the list. When I do that, all shapes will reset the data field corresponding to the list. Is there a way to avoid this, without using external data?