My guess, somebody needed a tax loss on this stock to offset other gains. There's a different strategy out there this year. Hold any gains until next tax year hoping to get better tax rates. Unless, you have some stocks that you can sell at a loss to offset any gains this year. Problem with holding onto shares until next year there's no guarantee the gains will still be there.
So,I'm not surprised to see this type of volume(and price) this close to the end of the year.
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