I have two formulas reference each other for one function: A user can input data into one cell and have it converted into a different form of currency in the other cell, and vice versa. The conversion is done by taking the input, referencing a coefficient and either dividing or multiplying by it. The problem that lies within this, is that one currency inflates in value very quickly either up or down, so the referenced coefficient changes from day to day.

This is where the problem starts. How can I get the E and F columns to not update once data is entered into them? Essentially, I need a way to lock them in to the data that's entered into them after the user finishes inputting data. I need that data to not update when the coefficient is changed on the next day.

See image for reference: http://i.imgur.com/JphCu.jpg

If am not being clear enough, please let me know and I will do my best to clarify. I am still pretty new to OO and Excel, and am very open to any chance to learn!

Thank you for reading,
- SN