Nissan Juke is arguably one of those highly aerodynamically designed cars. With the hatch or coupe design like at the back, air flows in an airplane-wing like orientation and adding to a spoiler evens helps more with drag effect from air flow. Arguably, that is one of the reason why the Juke-R with the GTR 3.8L V6 engine was produced in just the same design as the famous Juke.