Question : Format IIF

Exoerts,
I get a #error for every CurrencyID not equal to 1,  For currencyID = 1 it returns the expected number.  Is there something wrong with the below?  
USDEquivalent: Format(Round(IIf([CurrencyID]=1,"",([tblLetterOfCredit]![Amount]*[tblCurrencyExchange]![ExchangeRate]))),"Currency")

thank you

Answer : Format IIF

USDEquivalent:
IIf([CurrencyID]=1,"",Format(Round([tblLetterOfCredit]![Amount]*[tblCurrencyExchange]![ExchangeRate]),"Currency"))