Please, next time you post something like this, weigh the tank empty, then fill and re-weigh before the drive, and after to ensure a proper measurement of how much fuel was used. Then get out and measure the distance to and from work with one of those measurement wheels on the end of a stick, maybe 2 to ensure accuracy. Also please note throttle position any time it changes, idle time, air temperature, fuel temperature, tire inflation, water separator levels, humidity, barometric pressure, intake temps, egts, your air conditioner settings, if your headlights were on or off, and any time you used your blinkers.
Thanks.