Form 1116 Worksheet Error for "Deductible other interest

Form 1116: Foreign Tax Credit Computation Worksheet is asking to enter a frivolous entry in Part 1 - Taxable Income Line 4, b : "Deductible other interest" (1) C: Adjusted basis if total investment assets.

 

As I have no "Deductible other interest", why would the "Allocation ratio" of "1" gets entered? This is causing the above-mentioned issue