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How Currencies Are Displayed in Workfront

The currency sign/symbol is displayed only for the default currency in the system. All other currencies (project or user specific ones) are showing up in currency codes as the system assumes that the users know the default currency symbol but may not know the symbols for other currencies.
For instance, if you have British Pound set as your default currency and American Dollar set as the currency for a particular project the system will show £ for pounds and USD for dollars.