Why is my Kia Niro's gas mileage decreasing?

I recently noticed that my Kia Niro's gas mileage has decreased significantly. I used to get about 50 mpg, but now I'm only getting around 40. What could be causing this decrease in fuel efficiency?

Have you checked your tire pressure? Underinflated tires can greatly reduce fuel efficiency.

It could be due to your driving habits. Avoiding rapid acceleration and braking can help improve your gas mileage.

When was the last time you changed your air filter? A dirty air filter can reduce fuel efficiency by up to 10%.