Imagine somebody who discovered secondary-school maths troublesome being grilled about logarithms. That’s how numerous fairness buyers look when you ask them about currency risk. It isn’t as a result of the query is novel: any consumer can spot that the share worth of an abroad agency, or one doing enterprise throughout borders, should rely on foreign-exchange (FX) charges. It’s as a result of it’s simple to pose, however maddeningly exhausting to reply. Forecasting earnings is already a ache. It turns into a lot worse when the duty is to make forecasts for every firm in a portfolio, earlier than splitting prices and revenues by maybe a dozen currencies, after which netting all of it off in opposition to hedging preparations made years in the past by a now-retired treasurer. Unsurprisingly, such evaluation is commonly dumped within the “too exhausting” bucket.