What are you referring to? Are you talking about the taxpayer's contribution to his 403b? If so you need to scroll down between q and r and there is a worksheet to keep track of the employee's contribution to the plan. It is called the "pickup contribution amount "smart" worksheet". (all of these worksheets think they are so smart!). Usually you would do this in the first year. Then eventually you will see the 1099R says ESP used which means it is all taxable from that point forward.

I hope this is what you are referring to. Otherwise delete the response.