With almost every decision
in life, people tend to focus on the positive, and minimize the negative. Think about buying a house - what entices
you first? Usually, it is curb appeal, and if your first impression is favorable, you'll tend to minimize negatives,
like maybe the amount of rehab the house needs on the inside.
It is the same thing with trading systems
or strategies. Most people tend to focus on the rate of return, or maybe even the winning percentage, and if that looks
good, they'll downplay the negatives, like the drawdown. For those of you who do not know, "drawdown"
is the amount of money lost from the highest equity point. It might be a temporary loss, but you'll have to endure
it if you trade the system. Low drawdowns are best, but they are usually tied to low returns (think of interest on a
bank account).
When looking at a trading system, signals, or service, your focus should be on downside risk
- drawdown is a great way to measure it.
Drawdowns are extremely difficult for people, especially
those among us who follow an advisor or trading signal recommendations in a web service or a newsletter. Since the subscriber
did not develop the system (assuming there even is a "system," not just random selection of trades under the guise
of an established method), they do not know what to expect. The only thing they can see is what is shown in the trading
record, which is usually only a small snippet of time in the system's history (if the developer did the right thing, and
used at least a few years of history to test out his idea).
And, if that record is not independently verified
and auditable, then even that history should be regarded with suspicion. There are plenty of services out there that
independently verify trading records, and they are definitely worth using.
So, what is a good way to evaluate
a trading system, newsletter or service? Here is what I'd recommend to potential subscribers of ANY system:
1. Make sure the trading history you see is actually representative of what is being traded today by the developer. There
are a lot of knucklehead developers who will significantly change a system midstream, yet keep the same system! So, when you
look at an equity curve, you'll be seeing the combined results of 2 or more systems. That is ridiculous at best, misleading
and unethical at worst.
2. Before you subscribe to any service or system, find out what the historical maximum
drawdown was. As a rule of thumb, multiply that by 1.5. Could you handle that amount of drawdown right off the bat? If not,
then you shouldn't subscribe.
3. If you have the ability, put all the trades in a Monte Carlo Simulation
and see what shakes out. Monte Carlo simulation is a technique that introduces randomness into future trading results
- since the past is never repeated exactly, it is a good way to simulate possible future results. You will be able to see
drawdowns in terms of probabilities. So, for example, you might find out that trading system X has a 50% chance of having
a drawdown greater than 30% in the first year. It may have this severe of a drawdown, it may not, but the point is at least
you'll have some better data to go off of.
4. BEFORE you subscribe, determine your walk way point, and
stick to it. Your thinking might be like this:
"I checked with the developer, and he has not changed his system
since introduction. A check of his trades confirms that he is trading the same way he always has. His independently verified
records show he had a 20% drawdown. Developer's hypothetical history shows a 25% drawdown, and Monte Carlo sim shows a
50% chance of a max drawdown of 30% in the first year. So, I'll take the worst case of them all, and multiply by 1.5.
That gives me 1.5*30 = 45% drawdown I should be ready for. That is too much drawdown for me, so I either need to add
capital to the account, or not trade this system. Looking at the results, if I double my initial capital, I still get a very
good rate of return, and I can withstand a 22.5% drawdown. If that drawdown gets hit, I am out - NO QUESTIONS ASKED. Otherwise,
I stick to the system!"
The major point is: don't be sucked in by the fancy curb appeal of net
profits or rate of return. Dig deeper, and look at the potential risk, especially drawdown. It takes more effort,
but in trading there is no easy way out. Those who try the easy way usually end up losing all their money.