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The AdServer refreshes the exchange rates for all supported native currencies from https://www.ecb.europa.eu/stats/policy_and_exchange_rates/euro_reference_exchange_rates/html/index.en.htmlcurrencylayer.com/ each day at Midnight UTC.
These rates are then used once we have them available and until such time as we do the next refresh in 24 hours.
Also, note that the AdServer does not round off the exchange rates either higher or lower in any way.
We use the actual exchange rate we get from the Exchange Rate Source.
To illustrate, all the auctions conducted from 6/1/2021 00:00:00 UTC through 6/1/2021 23:59:59 UTC will use the same exchange rates converted to USD throughout the day.
Once we refresh the exchange rates on 6/2/2021 00:00:00 UTC, the exchange rate used going forward will be the exchange rates that was acquired as of 6/2/2021 00:00:00 UTC.
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