How Much of Your Return Is the Euro–Dollar Rate? The Currency Effect, With an Example

The answer: two returns, multiplied

When you hold a US stock in a euro account, your result in euros comes from two things that move independently:

1. The local return — what the stock did in its own currency, dollars.
2. The currency effect — how much the euro value of each dollar changed while you held it.

They multiply rather than add:

Return in euros = (1 + return in dollars) × (1 + change in the euro value of a dollar) − 1

The same goes for a British share priced in pounds or pence, or any holding listed in a currency other than the one you count your money in.

A worked example: +10% in dollars, a 5% weaker dollar

You buy 10 shares of a US company at $100 each. A year later the shares are at $110, and the dollar has fallen 5% against the euro.

• Return in dollars: +10.0%.
• Currency effect: −5.0% (each dollar is worth €0.8636 instead of €0.9091).
• Return in euros: 1.10 × 0.95 − 1 = +4.5%, or +€40.91.

To split those €40.91 into "the stock" and "the dollar":

• From the stock: the $100 price gain, valued at the rate when you bought: $100 × 0.9091 = +€90.91.
• From the dollar: the change in the rate, applied to what the position is worth in dollars today: $1,100 × (0.8636 − 0.9091) = −€50.00.
• Together: €90.91 − €50.00 = +€40.91, exactly the change in euro value.

Why +4.5% and not 10% − 5% = 5%? Because the weaker dollar hits the $100 you gained as well as the $1,000 you put in. That is the missing half point, and on larger moves the gap grows.

The same arithmetic works in reverse: in a year when the dollar strengthens 5%, the same +10% in dollars becomes +15.5% in euros, and about a third of your gain has nothing to do with the company.

How to do it for your own portfolio

For each holding:

1. Take each purchase separately. Shares bought at different times were bought at different exchange rates. For each purchase, note the date, the price in dollars and the rate.
2. Use the rate your broker booked. A DEGIRO Account Statement records the exchange rate applied to each foreign order in its FX column (what every column means). That rate, not the day's market rate, is what your euros actually bought.
3. Value the price change at the purchase rate (the stock's part) and the rate change on today's dollar value (the currency's part), as in the example.
4. For shares you sold, stop at the sale: the currency effect is the change in the rate between purchase and sale, applied to the sale proceeds in dollars.
5. Add up per holding, then for the portfolio. The sum of the currency parts is how much of your return the euro–dollar rate delivered.

Doing this in a spreadsheet is very doable for a handful of positions bought once. With regular purchases, partial sales and dividends, it grows quickly — which is what a performance tool is for.

How StockDashes shows it

Checked in the StockDashes code on 16 October 2026:

• The performance page's Currency Impact card shows the currency effect for your portfolio as one figure, in euros or US dollars, for the period you choose. It says whether it was a tailwind (the dollar strengthened) or a headwind (the dollar weakened), and splits it into open positions and realised ones (shares you sold).
• It is calculated per purchase, the way described above: for shares you still hold, today's value in their own currency times the change in the exchange rate since you bought (or since the start of the period); for shares you sold, the sale proceeds times the change in the rate up to the sale. In a euro view, where your DEGIRO Account Statement records the rate of an order, that booked rate is used; otherwise the day's closing rate.
• Next to it, a EUR/USD card and chart show the rate since your start date, and your time-weighted return in euros is shown against the S&P 500 total return in euros. That return includes the currency effect, so the Currency Impact card tells you how much of it came from the dollar.
• Coverage: the return covers US-listed holdings and European shares priced via their US listing. Your other holdings stay in your portfolio by name and are listed separately on the performance page, so you always see exactly what your return is built from.

Want to see your own split? Export your DEGIRO Account Statement (here's how) and import it into a free StockDashes account — the file is read on our server and not stored.

Create a free account and import your statement →

Frequently asked questions

How do I calculate the currency effect on my return? Value the change in the share price at the exchange rate when you bought, and the change in the exchange rate on what the position is worth in its own currency today. The first part is the stock's return, the second the currency effect; together they equal the change in euro value.

Does a weaker dollar lower my return in euros? Yes, for holdings priced in dollars: the same dollar value is worth fewer euros. A stronger dollar adds to your return in euros by the same mechanism.

Why isn't my euro return simply the dollar return minus the currency move? Because the two multiply. The currency move also applies to your gain, not only to what you put in: +10% in dollars with a 5% weaker dollar is +4.5% in euros, not +5%.

Is the currency effect included in DEGIRO's profit and loss? Yes. DEGIRO's Total P/L in euros includes currency fluctuations, combined with price gains, dividends and fees in one figure. Splitting out the currency part is what the calculation above, or a performance tool, does.

Which exchange rate should I use? The one your broker applied to each order. In a DEGIRO Account Statement it is in the FX column; using today's rate for a trade from years ago gives a wrong split.

The short version

Your return in euros on a US stock is the stock's return in dollars and the dollar's move against the euro, multiplied: +10% and −5% make +4.5%. Value the price change at the rate you bought at and the rate change on today's dollar value, and the euro result splits exactly into "the stock" (+€90.91 on €909) and "the dollar" (−€50.00).

See your currency impact →