GreenBrier is a premium industrial in a hot segment of the Market. Over the last couple of years it has been on a tear, advancing more than 100%. Now there are Mutual funds and other institutional investors who are sitting on healthy gains. Note that fundamental story has NOT changed a bit. This is a pure rush to lock in profits - Look at this selloff. This demonstrates pure, raw power of desire to lock in PROFITS!
Notice how A/D line has predicted waning interest before the price topped out.