Why is the mpg on my Ford S-Max decreasing?

I've had my Ford S-Max for a few years now and have always been happy with its fuel efficiency. However, lately I've noticed that the mpg seems to be decreasing. What could be causing this and how can I improve it?

It's possible that your tires may need to be inflated or replaced. Proper tire pressure is important for fuel efficiency.

Another reason could be a clogged air filter. This can affect the engine's performance and therefore, decrease the mpg.

Have you had your car serviced recently? Regular maintenance can help keep your car running efficiently.