Kamui Kobayashi says he was pleased with his rookie Formula 1 season, despite some difficult times early on.
The 24-year-old Japanese finished 12th in the championship with a best result of sixth at Silverstone, while his Sauber team finished eighth in the constructors.
"We had a lot of ups and downs, but overall we had a good season," Kobayashi said. "In the beginning, we were struggling a lot. This was a pretty bad time. It was hard and it was very difficult to recover from this situation during the season because nowadays there is no testing.
"Despite this, toward the end of the season we were much stronger. The team did a great job to recover from this and I want to thank them for all their work."
Kobayashi says Sauber's target for next season is to finish higher in the constructors' championship, having finished 24 points shy of the battle for sixth between Williams and Force India.
"My personal aim is to make zero mistakes," he added. "For the team, I hope we will have a good car and be able to fight for points on a regular basis to improve our position in the championship."