Has your gas mileage gone up or down?

Just need to know if your vehicle's gas mileage has gone up or down since the addition of 10% ethanol to gas. Could you include the vehicle year and make. Just doing independent research for a paper on the effects good or bad on ethanol addition to gasolenine. Thanks for your cooperation. Also need detailed estimates exp. from 16 mpg to 13 mpg. Thanks.