My average is a bit over 42 MPG since I took delivery of my 2012 "Justa Cooper".
https://www.fuelly.com/driver/fenimo...per?fu=4714841
At first, I was doing fairly aggressive hypermiling, but now I've scaled my efforts back. I still don't accelerate very hard (60-70 LOD, usually), and I generally don't go over 60 MPH, and I will turn my engine off at lights. But I'm not doing much engine-off coasting, nor am I trying too intently.
I posted a best tank of just over 50 MPG, and have now settled into the low 40s. So staying above 40 is indeed possible, just with driving techniques.
-soD