This guide explains how to find the currency conversion used in a query and it is applied.
The conversion can be found by looking at the key figure and choosing "display", then going to the "Conversions" tab :

The important field is the "Conversion Type .
If the key figure doesnt have any vale in this conversion type, but is converted when you run the report, it means that this key figure is calculated using another key figure which has a conversion. The calculated/restricted key figure will inherit the conversion from the key figures used in it's formula
If a conversion is applied to a key figure and then that key figure is used in calculating another key figure (Restricted Key Figure or Calculated Key figure), the new key figure will also be converted ! |
The "Target Currency", which defines to which currency the conversion will be done can have several values :
Once you have found the conversion type used in the key figures, log in BW SAP and launch transaction RSCUR.
Enter/select the Currency Conversion Type :

There are several information that need to be taken into account :
The Exchange Rate Type used : this defines which are is going to be used. We can later check the actual amount.

You can find in the public BW Exchange rate wiki page a list of the rates found in BW with their meaning : BW Currency Conversion
The Time Reference used : this is time element that will be used to apply the rate.
It can be either Fixed : for example we apply the rate available at current date.
Or it can be variable : for example based on the date in each line/document. 
In this example the time reference used is the "0FISCPER" with "End Of Period". This means that when BW does the conversion it will look for each line what is the fiscal period and then look for the exchange rate value available at that fiscal period.
The Target Currency : If "Target Currency Selection with Translation" then the currency will have to be selected in the query designer (via variable or fixed). Otherwise it can be fixed or via a variable.

Once you know the Conversion Rate Type used we can check the actual value used.
For that launch transaction SE16 and enter table name "TCURR" (which stores all the conversion rates) :

Enter the exchange rate type and you can see the values :

Example of result : 