No, those are reasonable fuel trim numbers, overall. At the bottom of the page, there's a new video about fuel trim and what it means (along with a live demo) from thecarcarenut. It will help you understand what short and long term fuel trims represent. The short term fuel trim is only of interest at idle, with the car warmed up, and in closed loop. 

There are number of things that could contribute to lower fuel numbers. None of them is determinative, but collectively, they might help. If they seem overly simple, please bear with me.

1. The simplest thing is to check the air in your tires, which is what Scotty demonstrated, even yesterday, as he prepared his Matrix for a trip to upstate New York and New England. If they are low, they will drag down fuel efficiency;

2. Check your air engine filter. If it's dirty, replace it;

3. Clean both the MAF and the throttle body.

4. Test for vacuum leaks. Scotty has videos on this. He used a cigar in one, carb cleaner in another, to look for leaks.

5. Check your brake calipers and pads. It might be that one caliper/pad is dragging along the rotor. Even if it's just slightly, it will bring down your fuel economy.

This is the simple and cheap approach, and it's often effective. Begin with the basics, and work outward from there.

Good Luck.

https://www.youtube.com/watch?v=fDwq4OR6FT8

What fuel economy were you seeing before?  How long have you been seeing these lower mpg numbers?  Have you looked through Scotty’s videos on things to try to address the lower fuel economy?

https://m.youtube.com/c/ScottyKilmermechanic/search?query=Fuel%20economy