Disable STOCK() price update in Numbers before opening file

I'd like to open an old Numbers file that contains calls to the current stock price function and see all the values that it held as of the date it was saved. Can I disable the function somehow before opening the file? I've tried disconnecting from the network before opening the file, but somehow the values seem to be magically updated anyway. Should inserting the date the file was saved in all the calls to the stock price function restore the data correctly?