You should evaluate foreign market results based on your domestic currency. Here is the US centric example. 1. You exchange Dollars for Euros 2. You buy a sto

You should evaluate foreign market results based on your domestic currency. Here is the US centric example. 1. You exchange Dollars for Euros 2. You buy a stock in Euros 3. You hold the stock in Euros for a period of time 4. You sell the stock in Euros 5. You exchange your Euros for Dollars. The difference in the exchange rate in step 1 and 5 can have a very large impact on your total return, often times a larger impact than step 3.