Which gas to fill in the Opel Corsa D

The vehicle operating instructions indicate that the fuel used for the Opel Corsa D fuel shall be at least 92 octane number 92. In terms of fuel efficiency, there is no difference between 92 and 95. The engine control unit is rebuilt using either fuel and the average flow rate (in monetary terms) remains approximately the same, so the A-92 actual flow rate is higher.