How to read currency pairs and exchange rate charts

If you see 10.20 next to the dollar in the Morocco market, ask what currency that number is in and how many dollars it buys. Identifying the unit helps you compare two charts or reverse a conversion without mixing up the currencies. It also explains why the number changes when you select a different country on the dashboard.

Which currency comes first?

The pair USD/MAD expresses the value of one US dollar in Moroccan dirhams. The dollar is the base currency and the dirham is the quote currency. At a hypothetical 10.20, 50 dollars has a reference value of 510 dirhams. To convert 510 dirhams in the opposite direction, divide by 10.20 and get 50 dollars. The price of a dirham in dollars is the reciprocal, about 0.09804 dollars per dirham in this example.

Confirm that the published price is for one unit. Another source may display the inverse direction or use 100 units as its convention. A reliable way to avoid mixing them up is to write the units beside the number, such as “dirhams per dollar.” Keep the available precision through the calculation and round the result at the end, especially when inverting small numbers or converting a large amount.

Calculate a cross rate through the dollar

Suppose the same source publishes 10.00 dirhams per dollar and 0.90 euros per dollar on the same observation date. Divide dirhams per dollar by euros per dollar to get dirhams per euro. That is 10.00 divided by 0.90, about 11.11 dirhams per euro. You can verify the direction by first converting 100 euros to about 111.11 dollars, then multiplying by 10.00 to get about 1,111.11 dirhams.

Souq Al Yom uses Frankfurter reference data and derives a conversion when rates for both currencies are available. When working out a cross rate yourself, look for observations from the same day. Combining one day’s euro observation with another day’s dirham observation can give you a number that represents neither date accurately.

What does a rising line mean?

Select a market, then choose the dollar or euro series. The horizontal axis shows observation dates and the vertical axis shows the rate in the selected market’s currency. If the dollar rises from 10.00 to 10.20 dirhams, a dollar corresponds to 0.20 more dirhams between those observations. The relative change is 0.20 divided by 10.00, or 2%. Reverse the pair and the movement is expressed in dollars per dirham, so it reads differently.

Use the 7-, 30- or 90-day window for the period you want to examine and check the values and dates of the plotted points. A tight vertical scale can make a small move look large. Work out the difference from the numbers. If a holiday or another gap separates observations, a line segment connects the published points. The most recent observation date can vary by currency.

A quick check for any chart reading

1. Confirm the market and quote currency before comparing two values.
2. Record the first and last observation dates. Check the dates displayed if today is missing.
3. Subtract the first value from the last, then divide by the first to get the relative change.
4. Check the conversion direction with the currency converter and get the executable price and fees from the transaction provider.

The chart shows the history of published observations. To track a pair over time, compare equivalent periods using the same currency so the direction of the move stays meaningful.