Reportedly bear expenditure for an old Peruvian empire (4)

I believe the answer is:

inca

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But I can't explain it at all! Could you help me understand?

(Other definitions for inca that I've seen before include "Old person in race" , "S. Am native, lord in Quechua" , "Old South American native" , "Former emperor" , "Ancient Peruvian Indian" .)

I've seen this clue in The Hindu.

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