The best method to determine the location of a protective stop-loss order is derived from cyclical analysis. Long positions are protected with sell-stop orders (GTC) based on the previous cyclical low while short sale positions have buy-stop orders (GTC) based on the stock's previous cyclical high. Locating the most recent previous cyclical low from the time a position was originated and deducting 1/2 of a point produces the sell-stop. In the example below, the initial sell-stop for a long position initiated for Aetna (AET) in mid-January would have been 46.50.
Stops should remain unchanged if the price of the stock moves lowers. However, as the price of the stock moves higher, the stop should be adjusted upward. The following chart shows the proper placement of sell-stop orders as AET moved up in price over the January-April time frame.