I am in Houston as well and am getting about 16.5 around town and as much as 20 on road trips if I keep it at 65 (not too often). I have been getting between 17 and 18 for the last few weeks and 5000 miles driving 70 - 80, as I cross the state. It goes down close to the 17 make at 80 for the streches of I-10 and I-20 that have the limit that high in west Texas.