2011 gen 3 w/ 2018 gen 4 engine

I recently put a 4th gen 2018 engine in my 3rd gen 2011 base edition. It came with a new radiator, new water pump, new EGR cooler and valve. The engine only had 29 k miles. I also have a fairly new catalytic converter.

My question is...why is my MPG the same as before? I was getting 43 MPG with my 3rd gen. But, I am getting around 43 with the newer improved engine. Obviously, it is not the engine or the EGR. Also, my batteries are strong. I have cleaned the battery filter regularly. Everything is well maintained. Many of my friends have 3rd gen Prius and are getting over 50 MPG. I have not gotten over 50 MPG regularly since I bought the car at 49K. For the first year it hovered around 48 MPG. Now it goes between 43 and 48 MPG depending on the situation. Those numbers are about the same with the new engine. It has 470K total miles. What can I do to improve this?