Why is the Kia Picanto's fuel efficiency declining?

I've noticed that the fuel efficiency of my Kia Picanto has been decreasing over time. I always make sure to properly maintain my car and drive efficiently, so I'm not sure why this is happening. Can anyone provide some insight into why this might be happening and how I can improve my car's fuel efficiency?

Caroline, have you checked your tire pressure recently? Low tire pressure can significantly decrease your car's fuel efficiency.

Make sure you're using the right grade of motor oil for your Kia Picanto. Using the wrong type of oil can negatively impact fuel efficiency.

Caroline, have you noticed any strange noises or vibrations while driving? It's possible that there could be an issue with your engine that is causing the decrease in fuel efficiency.