Why is my Nissan X-Trail's gas mileage decreasing?

I've noticed that my Nissan X-Trail's gas mileage has been getting worse over the past few months. Any possible explanations for this and tips on how to improve it?

It could be due to a number of reasons such as low tire pressure, dirty air filters or a faulty oxygen sensor. Regular maintenance and proper tire inflation can help improve gas mileage.

Is your driving style more aggressive lately? Rapid acceleration and frequent braking can decrease gas mileage. Try to drive more smoothly and avoid idling for extended periods of time.

Another factor could be the quality of gasoline you're using. Try switching to a higher octane fuel if your Nissan X-Trail's engine requires it.