Measure how much exchange rates moved a period's TIV since the previous period. Returns the values per currency they were entered in (sites, amount in that currency, base-currency value, rate change and currency effect) and the currency effect per site and value key. Amounts are what each value counts toward TIV: as entered, except Business Interruption in a period that takes it as a base value, which is scaled by the site's BI period. The currency effect is the period's values at its own rates minus the same amounts at the previous period's rates.