Goal triggered by event with a value does not show the revenue

I defined a goal whenever a user fires an event. The event triggers with a value. On my project the event is fired by this javascript code:

_paq.push(['trackEvent', eventCategory, eventAction, eventValue]);

where eventValue is an integer. When I look in Matomo at the events list I see that the event was fired and when I open the second tab on the event list “Ereignisaktion” in German there are value listed.

Additionally I set a goal based on this event and I clicked the checkbox to use the event value a the revenue. The events show up as reached goals but no revenue is calculated, it stays 0 (zero). Does anyone have an idea what causes this?

Tobias Krause