Adjusted completion percentage takes into account factors outside of the quarterback's control in terms of completing passes. It accounts for dropped passes, passes thrown away, spiked balls, passes batted at the line of scrimmage and those passes in which a quarterback was hit as he threw. Ultimately, this gives a real indication of completion percentage on passes that can actually be caught, as opposed to a quarterback's completion percentage for a given game being tarnished by a load of receiver drops or other factors.