It is probably a good idea to keep the original value and the currency rather than converting them to dollars just the one time. This will allow you to recompute dollar figures based on currency exchange fluctuations.
Or are there any cases where a single job market spans two or more currencies?
Perhaps it would be useful to be able to view the results in any currency you desired. But already we're entering scope-creep territory :-)
Also, our bonuses are denominated in USD and then converted (or not) into whichever currency we prefer.