Box 14 represents taxes withheld for the state and box 16 represents the amount that is taxable to the state. If there are taxes being taken out for the state then the taxes must be taken out of a larger amount for which tax is due. That amount should be in box 16 and should be the same as the amount in either box 1 or box 2a.
When issuing a 1099-R there are several states that don't have any state taxes - in those cases there should be no information entered for boxes 14,15 or 16 anyway.
But if there is tax being withheld in box 14 then it has to be being withheld from a larger taxable amount in box 16. Without it the math doesn't make sense. So the program has to ask it.
@JSRRETIRED
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