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Trailing Stops
Written by Chuck LeBeau
Now that we have taken the necessary precautions to avoid catastrophic
losses by using disciplined money management stops, it is appropriate
to concentrate on strategies that are designed to accumulate and
retain profits in the market. When properly implemented these strategies
are intended to accomplish two important goals in trade management:
they should allow profits to run, while at the same time they should
protect open trade profits.
While their application is extremely wide, we do
not believe that trailing stops are appropriate in all trading circumstances.
Most of the trailing exits we will describe are specifically designed
to allow profits to run indefinitely. Therefore they are best used
with trend following type systems. In counter-trend trading, more
aggressive exits are more suitable. The when youve got
a profit, take it philosophy works best when you are trading
counter-trend, since the anticipated amount of profits is limited.
However, to take quick profits in a trend is usually an exercise
in frustration: we exit the market with a small profit only to watch
the huge trend continue to move in our direction for days or months
after our untimely exit. We therefore recommend using different
exit strategies based on the underlying market condition. We will
discuss the more aggressive exits later; for now we will concentrate
on exits designed to accumulate large profits over time.
A thorough understanding of trailing stops is critical
for trend-following traders. This is because trend following is
typically associated with a lower percentage of profitable trades;
which makes it particularly important to capture as much profit
as possible when those large but infrequent trends occur. Typical
trend followers make most of their profits by capturing only a few
infrequent but very large trends, while managing to cut losses effectively
during the more frequent sideways markets.
The rationale behind the use of the trailing stop
is based on the anticipation of occasional extremely large trends
and the possibilities of capturing substantial profits during these
major trends. If the entry is timely and the market continues to
trend in the direction of the trade, trailing stops are an excellent
exit strategy that can enable us to capture a significant portion
of that trend.
The trailing stops we will describe in this and
following articles have similar characteristics that are important
to understand as we use them to design our trading systems. Effective
trailing stops can significantly increase the net profits gained
in a trend-following system by allowing us to maximize and capture
large profitable trades. The ratio of the average winning trade
to the average losing trade is usually improved substantially by
the use of trailing stops. However there are some negative characteristics
of these stops. The number of profitable trades is sometimes reduced
since these stops may allow modestly profitable trades to turn into
losers. Also, occasional large retracements in open trade profits
can make the use of these stops quite difficult psychologically.
No trader enjoys seeing large profits reduced to small profits or
watching profitable trades become unprofitable.
The Channel Exit
The simplest process for following a trend is to
establish a stop that continuously moves in the direction of the
trend using recent highest high or lowest low prices. For example,
to follow prices in an uptrend, a stopmay be placed at the lowest
low of the last few bars; for a downtrend, the stop is placed at
the highest high of the last few bars. The number of bars used to
calculate the highest high or lowest low price depends onthe room
we wish to give the trade. The more bars back we use to set the
stop, the more room we give the trade and consequently the larger
the retracement of profits before the stop is triggered. Using a
veryrecent high or low point enables us to take a quick exit on
the trade.
This type of trailing stop is commonly referred
to as a Channel Exit. The channel name comes
from the appearance of a channel formed from using the highest high
of X bars and the lowest low of X bars for shortand long exits respectively.
The name also derives from the popular entry strategy that uses
these same points to enter trades on breakouts. Since we are focusing
on exits and will be using only one boundary ofthe channel, the
term channel may be a slight misnomer, but we will continue
to refer to these trailing exits by their commonly used name.
For most of our examples we will assume that we
are working with daily bars but we could be working with bars of
any magnitude depending on the type of system we are designing.
A channel exit is extremelyversatile and can work equally well with
weekly bars or five-minute bars. Also keep in mind that any examples
referring to long trades can be equally applicable to short trades.
The implementation of a channel exit is very simple.
Suppose we have decided to use a 20-day channel exit for a long
trade. For each day in the trade, we would determine the lowest
low price of the last 20 daysand place our exit stop at that point.
Many traders may place their stops a few points nearer or further
than the actual low price depending on their preferences. As the
prices move in the direction of the trade, thelowest price of the
last twenty days continually moves up, thus trailing
under the trade and serving to protect some of the profits accumulated.
It is important to note that the channel stop moves only in thedirection
of the trade but never reverses direction. When prices fall back
through the lowest low price of the last twenty days, the trade
is exited using a sell stop order.
The first and obvious question to answer about channel
exits is how many bars to use to pick the exit point. For example,
should we set our stop at the lowest low of 5 days or the lowest
low of 20 days, or someother number of days? The answer depends
on the objectives of our system. A clearly stated set of objectives
for the system is always very helpful at these important decision
points. Do we want a long-termsystem with slow exits or do we want
a short-term system with quicker exits? A longer channel length
will usually allow more profits to accumulate over a long run if
there are big trends. A shorter channel willusually capture more
profits if there are smaller trends. In our research, we have found
that long-term systems generally work well with a trailing exit
at the lowest low or the highest high of the last 20 days or more.For
intermediate term systems, use the lowest or highest price of between
5 to 20 days. For short-term systems, the lowest or highest price
of between 1 to 5 days is usually optimal.
Trailing stops with a long-term channel accumulate
the largest open profits if there is a sustained trend. However
this method will also give back the largest amount of open profits
when the stop is eventuallytriggered. Using a shorter channel can
create a closer stop in order to preserve more open trade profits.
As can be expected, the closer stop often does not allow profits
to accumulate as nicely as the longerchannel, and often causes us
to be prematurely stopped out of a large trend. However, we have
noticed that a very short channel length of between 1 to 3 bars
is still highly effective in trailing a profitable trade in arunaway
trend. The best type of channel exit to use in a runaway trend is
a very short channel, for example 3 bars in length. We have observed
that this exit in a strong trend often keeps us in a trade until
we areclose to the end of the trend.
It appears that there is a conflict of exit objectives
here. A longer channel length will capture more profit but give
back a large proportion of that profit; a shorter channel length
will capture less profit, but protect moreof what it has captured.
How can we resolve this issue and create an exit that can both accumulate
large profits, as well as protect these profits closely? A very
effective exit technique calls for a long-term channelto be implemented
at the beginning of the trade with the length of the channel gradually
shortened as larger profits are accumulated. Once the trade is significantly
profitable, or in a strongly trending move, the goalis to have a
very short channel that gives back very little of the large open
profit.
Here is an example of how this method might be implemented.
At the beginning of a long trade, after setting our previously described
money management stop to avoid any catastrophic losses, we will
trail a stopat the lowest low of the last 20 days. This 20-day channel
stop is usually far enough from the trade to avoid needless whipsaws
and keep us in the trade long enough to begin accumulating some
worthwhile profits.At some pre-determined level of profitability,
which can be based on a multiple of the average true-range or some
specific dollar amount of open profit, the channel length can be
shortened to take us out of the tradeat the lowest low of 10 days.
If we are fortunate enough to reach another higher level of profitability,
like 5 average true ranges of profit or some other large dollar
amount, we can shorten the channel further so thatwe will exit at
the lowest low of 5 days. At the highest level of profitability,
perhaps a very rare occurrence, we might even be able to place our
exit stop at the previous days low to protect the great profit
we have accumulated. As you can see, this strategy allows plenty
of room for profits to accumulate at the beginning of a trade and
then tightens up the stops as profits are accumulated. The larger
the profits, the tighter ourexit stop. The more we have, the less
we want to give back.
There is another way of improving the channel exit
that is worthwhile to discuss: this is to contract (or expand) the
traditional channels using the height of the channel, or some multiple
of the average true range. How this might work is as follows: Supposing
you are working with a 20-day channel exit. First you calculate
the height of the channel, as measured by the distance between the
highest 20-day high and the lowest 20-day low. Then you contract
the channel by increasing the lowest low value and decreasing the
highest high value previously obtained to determine the exit points.
For instance, in a long trade, you could increase the lowest low
price by 5% of the channel height or 5% of the average true range,
and use that adjusted price as your exit stop. This creates a slightly
tighter stop than the conventional channel. More importantly, it
allows you to execute your trade before the multitude of stops that
are already placed in the market at the 20-day low.
The last point can be considered an important disadvantage
of the channel exit. The channel breakout methods are popular enough
to cause a large number of entry and exit stops to be placed at
previous lowest low and highest high prices. This can cause a significant
amount of slippage when attempting to implement these techniques
in your own trading. The method of adjusting the actual lowest low
or highest high price by a percentage of the overall channel height
or the average true range is one possible way to move your stops
away from the stops placed by the general public and thereby achieve
better executions on your exits.
by Chuck LeBeau
Systems Traders Club
www.traderclub.com
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