It does sound low. Expecting a 'break in' to happen somewhere down the road isn't really true anymore since the engines are pre broken in at the factory. Even though i live in CA it has been rainy and cold at least for here and i never got below 42 mpg over any trip even if it was stop and go and city only. Apart from anything being wrong with the car check your driving habits to see if that makes a difference - gradual acceleration and coast a bit more into stops, keep a steady speed on highways and try to stay at 65 - 70mph.