What it means
O'Neil built a career on studying the traits of stocks that went on to rise strongly, using historical data to look for common patterns. He founded a research firm in the 1960s, and in the 1980s he launched a newspaper that became Investor's Business Daily.
Both aimed to give investors data rather than opinion. His CAN SLIM approach is an acronym for seven factors.
C stands for current quarterly earnings, A for annual earnings growth, N for something new such as a product or a price high, and S for supply and demand of the shares. L stands for leader rather than laggard, I for institutional sponsorship and M for the direction of the overall market.
The method sits between fundamental analysis, which studies a company's earnings and business, and technical analysis, which studies price charts. A stock must have strong profit growth and also show the price behaviour of a leader, often breaking out from a base pattern.
This is why his ideas appeal to investors who want evidence from both the accounts and the market. A central part of his teaching is risk control.
He urged investors to sell any stock that falls a fixed percentage, often 7% to 8%, below the purchase price, so that small mistakes do not grow into large ones. The rule is simple to follow and is a good example of fixing the exit before the entry.
Like any method, CAN SLIM does not guarantee profits, and it can perform poorly when the market turns against growth stocks. Critics point out that backtested patterns may not repeat and that strict stop rules can sell positions just before a recovery.
Readers should treat it as a disciplined framework and not a promise. The approach is also a useful lesson for non-specialists in how to build a repeatable process.
It turns the vague idea of finding a good stock into a checklist that can be tested, reviewed and improved, which is the same discipline finance teams apply to budgeting or credit approval. Writing the rules down before the market moves reduces the pull of emotion.
In practice
Real-world examples.
Example
A retail investor uses CAN SLIM to screen for companies whose quarterly profit has risen sharply and whose share price is close to a new high. She narrows the list to three firms and checks that the overall market is rising before buying.
Example
An investment club buys a stock that falls 8% below its purchase price, and its rules require selling. Even though several members feel the stock will recover, the club sells and avoids a much larger loss when the price later keeps falling.
Example
A financial publisher builds a weekly stock ranking by comparing the earnings growth and relative price strength of listed firms. Readers use the ranking as a starting point before doing their own research.
Formula
Calculation
Stop-loss price = Purchase price x (1 - Maximum loss %)
Suppose an investor buys 200 shares of a company at $50, a total of $10,000, and applies a maximum loss of 8%. The stop-loss price is 50 x (1 - 0.08) = 50 x 0.92 = $46. If the price falls to $46, the investor sells and the loss is (50 - 46) x 200 = $800, or 8% of the amount invested.Case study
Seen in the real world.
Hartley Growth Partners is a fictional investment club, and this is an illustrative case. The members adopted a CAN SLIM-style checklist and a firm rule to sell any position that fell 8% below cost. In the first year, they bought 10 stocks with $10,000 each.
Four of the stocks hit the stop-loss and were sold with an average loss of 8%, costing $3,200 in total. Three rose and two of those gained more than 40%, so those two alone added more than 2 x 4,000 = $8,000, well ahead of the $3,200 of losses. The members noted that the stop-loss rule was uncomfortable to follow but kept their losses small.
Watch out
Common mistakes.
- Using only one part of the method, such as chasing price breakouts without checking earnings growth.
- Ignoring the market direction, when the M in CAN SLIM warns that most stocks fall when the overall market is falling.
- Moving the stop-loss lower when the price drops, which defeats the point of the rule.
Questions
People also ask.
What does CAN SLIM stand for?
It stands for Current earnings, Annual earnings, New products or highs, Supply and demand, Leader or laggard, Institutional sponsorship and Market direction.
Is CAN SLIM a guaranteed way to make money?
No, it is a framework that relies on history, and results vary with market conditions and the investor's discipline.
What is Investor's Business Daily?
It is a financial newspaper and data service that O'Neil founded, and it publishes stock rankings based on his ideas.
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