The wing sails with 3.1 percentage of essential wing area have observable efficiency in reducing induced drag. The factors of the induced drag were reduced by 20 percent.

总面积为3．1％基本翼面积的翼尖帆片对减少诱导阻力具有明显效果，诱导阻力因子减小20％左右。

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Now there are obviously going to be more factors than just parking spaces at play here, but certainly this is an observable phenomenon: go into any dilapidated inner city area and look around.

FORBES: Parking Lots Are a Waste of Space and a Drag on Growth