Fernando Alonso has given Ferrari an 8 out of 10 for the 2013 season so far.

The Spaniard is trailing Red Bull's Sebastian Vettel in the drivers' championship by 34 points, while Ferrari has admitted it is falling behind in the car development race.

"Now it is vital that we optimise the performance of our car, just as our rivals have managed to do, because we want to get back to fighting for the top places as soon as possible," said team boss Stefano Domenicali.

Nonetheless, in an interview with the German broadcaster RTL, Alonso said he is satisfied with his season so far.

"It has been good," he said, "so I think we can give it an eight (out of ten) -- a good score.

"Clearly we are not the fastest," the 31-year-old admitted, "but our car is very complete, so I would say I am satisfied."

Alonso has won twice but also finished second twice in 2013 so far, and he said trailing home the winner can sometimes be satisfying.

"Sometimes it (finishing second) is a great satisfaction, at other times a big disappointment," he said.

"There are never two results alike, as it depends on the circumstances and who is in first place.

"If your biggest rival is not the winner, it may be a very good result," Alonso added.