Donchian rules

Richard Donchian is known as the father of trend following. His original trend following ideas form the basis for all trend following success that has followed. Below in an excerpt from an article written in 1995 about his 5 and 20 day moving average system:

Title: Donchian’s five- and 20-day moving averages. 
Author: Richard Donchian
Publication: Futures (Cedar Falls, Iowa) (Magazine/Journal)
Date: November 15, 1995
Publisher: Oster Communications, Inc.
Volume: v24 Issue: n13 Page: p32: ISSN: 0746-2468

On Wall Street there are two conflicting adages:

1. “You’ll never go broke taking a profit.”

2. “Cut your losses short and let your profits ride.”

Experience has shown that in commodities trading, the first of these “old saws” is dangerous and misleading, while the second may well be regarded as the one lesson the inexperienced commodity trader should learn if he wishes to have a better-than-even chance to come out ahead.

Every well-designed, trend-following, loss-limiting method for trading in futures (or stocks) rests on the basic principle that a trend in either direction, once established, has a strong tendency to persist, at least for a time. Among the many trend-following approaches now in use are the Dow Theory, point-and-figure chart techniques, swing methods (other than the Dow Theory), trendline methods, weekly-rule methods and moving average methods. We’ll focus on moving average methods and, in particular, the comparatively simple five- and 20-day moving average method.

The Method
The rules for the five- and 20-day moving average method break down into two categories: general and supplemental.
General rules:


  • 1. The extent of penetration of the moving average is broken into units, depending on price level. For commodities selling over 400 (wheat, soybeans, silver), for example, a penetration of 40 cents is required (Donchian had six price classes in the days before interest rates and stock index futures).
  • 2. No closing penetration of the moving averages counts as a penetration at all unless it amounts to at least one full unit (39 cents in Rule 1 was not enough for penetration – it had to be 40 cents to count).
  • Basic Rule A: Act on all closes that cross the 20-day moving average by an amount exceeding by one full unit the maximum penetration in the same direction on any one day on a preceding occasion (no matter how long ago) when the close was on the same side of the moving average. For example, if the last time the closing price of cotton was above the moving average it stayed above for one or more days, and the maximum amount above on any one of the days was 64 points, then when the closing price of cotton moves above the moving average, after having been lower in the interim, a buy signal is given only if it closes above the average by more than 64 points (the unit in cotton is 0.10). This principle – the requirement that a penetration of the moving average exceeds one or more previous penetrations – is a feature of the five- and 20-day method that distinguishes it from other moving average methods.
  • Basic Rule B: Act on all closes that cross the 20-day moving average and close one full unit beyond (above or below, in the direction of the crossing) the previous 25 daily closes.
  • Basic Rule C: Within the first 20 days after the first day of a crossing that leads to an action signal, reverse on any close that crosses the 20-day moving average and closes one full unit beyond (above or below) the previous 15 daily closes.
  • Basic Rule D: Sensitive five-day moving average rules for closing out positions and for reinstating positions in the direction of the basic 20-day moving average trend are:
  • 1. Close out positions when the commodity closes below the five-day moving average for long positions or above the five-day moving average for short positions by at least one full unit more than the greater of a) the previous penetration on the same side of the five-day moving average, or b) the maximum point of any previous penetration within the preceding 25 trading sessions. If the distance between the closing price and the 20-day moving average in the opposite direction to the Rule D close-out signal has been greater within the prior 15 days than the distance from the 20-day moving average in either direction within 60 previous sessions, do not act on Rule D close-out signals unless the penetration of the five-day average also exceeds by one unit the maximum distance both above and below the five-day average during the preceding 25 sessions.
  • 2. After positions have been closed out by Rule D, reinstate positions in the direction of the basic trend a) when conditions in Rule D, point 1 above are fulfilled, b) if a new Rule A basic trend signal is given, or c) if new Rule B or Rule C signals in the direction of the basic trend are given by closing in new low or new high ground.
  • 3. Penetrations of two units or less do not count as points to be exceeded by Rule D unless at least two consecutive closes were on the side of the penetration when the point to be exceeded was set up.

Supplementary General Rules

  • 1. Action on all signals is deferred for one day except on Thursday and Friday, For example, if a basic buy signal is given for wheat at the close on Tuesday, action is taken at the opening on Thursday morning. The same one-day delay applies to Rule D close-out and reinstate signals.
  • 2. For signals given at the close on Friday, action is taken at the opening on Monday.
  • 3. For signals given at the close on Thursday (or the next to last trading day of the week), action is taken at the Friday (or weekend) close.
  • 4. When there is a holiday in the middle of the week or a long weekend, signals given at the close of sessions prior to the holiday are treated as follows: a) for sell signals, use weekend rules; and b) for buy signals, defer action for one day, as is done on regular consecutive trading sessions.

A word of caution
The five- and 20-day moving average method, and most other trend-following methods, for that matter, are not good to follow unless you are prepared to include in your program a sufficient number of futures to provide broad diversification. Risks are increased to an inordinate degree if you try to follow the method in one or just a few selected contracts.

The commodities that are in a pronounced trend and are not giving, new signals are frequently the ones in which the best results are attained. Therefore, in starting a new program it might be advisable not to wait for new signals but to take positions in the direction of prevailing trends in those not giving new activation advice. Because the markets are moving so wildly, however, it might be best to a) go in the direction of the trend only after one or more days of counter-trend movement, plus a day move in the direction of the basic trend, and b) to use an arbitrary stop on positions taken without waiting for new signals.

Remember, five and 20 days are not necessarily the best lengths for moving averages. And, most probably, the action rules themselves, as outlined above, could be refined and improved. Also, it may be that exponential moving averages, weighted moving averages, moving averages based on highs or lows or daily means, or some combination of all these, would produce superior results.

In this field of technical study it is probably safe to state that the beginning of wisdom comes when you stop chasing rainbows and admit that no method is perfect. When you find yourself willing to settle for any comparatively simple method that in tests over a long period of time makes money on balance, then stick to the method devotedly, at least until you are sure you have discovered a better method.


Richard Donchian worked at Shearson Lehman Bros. while developing his technical analysis and trend-following methods that today many traders use as the base of their systems. He also launched the first managed futures fund in 1948. Donchian died in 1993 at the age of 87.