Berlin 2822 average 108 pax per flight, not sure on breakdown of A319/320s used
Dusseldorf +1% (double the frequency of SXF yet has less pax!)
But I bet DUS had at least double the revenue per seat as SXF. Two completely different markets. DUS serves the Rhein-Ruhr industrial area, whilst Berlin, although the capital is still primarily a leisure destination.