If you do the math on the
If you do the math on the data available from Fuelly, the average fuel economy is about 37.4 MPG. This represents millions of miles in all driving conditions, weathers, and climates across the US. (Theoretically, the EPA estimate should match this average, but the EPA's methods still consistently overestimate by 5% for most vehicles).
Personally, I get 42-43 MPG in the summer and 37-38 MPG in the winter.