It depends on your goals.
If you need the money now for an important purpose then sell only as much as you need.
In normal investment you need to hold your stocks for as long as the fundamentals are good.
Company "fundamentals" are things like steady earnings each year instead of losses and very little long term debt so they won't get into financial trouble.
If the fundamentals go bad, sell and then buy good stocks.
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If you buy stock hoping that you can sell it for a quick profit because of the daily or monthly swings in price, then you are not investing. You are trying to guess better than the public (including the professionals) how the price will change. That is gambling.
When you buy and hold quality stocks over a period of time, the prices will go up for a real reason; the companies are earning money every year and becoming more valuable. This is investing.
?For when to hold:
Hold on to your stocks in good companies to allow them time to earn money for you. Except for your special goals, you don't ever want to sell.
If you save a portion of your income each payday and as it accumulates invest in sturdy stocks, then over the course of several years you can grow very wealthy indeed. It is like hiring someone to get a job and earn money for you, and then using that money to hire more workers. Your money grows exponentially .
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You're asking a timing question. Are you a trader? Are you sure you want a technical/timing answer? Some traders use a rule of thumb that if price doubles, they lighten up or get out. But this is in reference to short-term traders and your timing question, and has nothing whatsoever to do with investing.
Technically, since making a Double/Triple Bottom at 20, the stock has rocketed to 42. This pattern projected a price move to 36, so that is old news and gone. So to answer your question from a technical perspective or timing perspective, a trader would have sold at 36 or above. I think this is what you're referring to when you ask when to sell or buy given a price projection.
Notice the consolidation in price between the 34 and 38 level in July. This new level gives you an area of support in price. If it goes through that, it probably goes a lot lower. But it has backed off from the highs and is holding in that area, just above 38.
From a trading perspective, you could put a stop on your position at 37.50, or half of your position, and let the market tell you what to do rather than the other way around.
If you want to sell, I would try to get 40. If you want to buy more, this is a low-risk entry point with about $1 of risk.
Check out this chart of GM
http://finance.yahoo.com/echarts?s=GM+In...
Just draw a trendline from the low in 2012 to current levels. If it breaks this long-term uptrend line, then sell on the next rally, or when it breaks 37.50 (via your stop).
Don't day trade. If you are buying blue chip stocks, buy and hold and keep investing in it. Don't sell.
So if GM (General Motors) went up 7.45% do I buy shares, or if I own shares already do I sell those shares? If GM went down 29.54% do I buy shares or sell the shares I already own? If I bought more shares when GM went down, would I make money, because eventually GM stock would rise again?! Right? Please explain anything you think I REALLY need to know. Thanks for taking the time to read & answer my question, whether I pick you as best answer or not, your answer is greatly appreciated. God Bless you.
