Why is my Toyota Corolla's mpg decreasing?

I used to get great gas mileage in my Toyota Corolla, but recently it seems to be decreasing. What could be causing this and how can I improve it?

It's possible that you have a clogged air filter, which can significantly decrease your mpg. Try replacing it and see if that helps.

Have you changed your driving habits recently? Accelerating and braking too quickly can also lower your mpg. Try driving more smoothly and see if that makes a difference.

You may also want to check your tire pressure. If your tires are under-inflated, it can cause your gas mileage to drop. Make sure your tires are properly inflated.