Trading on a stock like this depends upon your timeframe IMO. I believe the long term trend is up but there are swings in the interim. In general I tend to trade around a core position. In this strategy I sell some when I think the stock is getting ahead of itself and buy some when the price drops too much. Often times that is easier said than done. The best strategy may vary for each person depending upon their ability to watch the market, tax considerations, etc.
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