Unless you use some VB code to determine the type of currency based on
the format, I think you'll need to add a second column that indicates
the type. Then you'll be able to use SumIF.

You are correct in pointing out that Excel thinks of these values as
numbers not currency values. Same with other numerical formats such as
dates and times. The format only dresses up the look. Underneath is a
number like most any other number.

- John