After owning my 2012 Focus SEL for a little over three months, I decided to test the fuel economy. Test conditions are highway only, no traffic lights or stop signs. This eliminates how busy the road is from the test. Test is with regular 87 octane brand-X gas with the 10 percent Ethanol.
At 70MPH, 33 miles per gallon.
At 60MPH, 42 miles per gallon.
Between 32 and 42MPH, no stop signs or traffic lights, just going with the flow, upwards of 52 miles per gallon.