The point is, we don't know how the data was presented by Amazon. I'd expect that the wages reported would be in USD to show how much it actually costs to the c

The point is, we don't know how the data was presented by Amazon. I'd expect that the wages reported would be in USD to show how much it actually costs to the company in the United States, and not some weird index. If they pay, say, R$ 30,000.00/year, I doubt they'd report anything other than the direct conversion to USD.