How many stocks should I own?
Choose a number of stocks and the years held. See what happened to random portfolios since 2006.
Data is updating. Try again later.
How to read the results
- Choose the number of stocks. Each portfolio puts the same amount in each stock.
- Choose how many years the portfolio was held.
- Read the four numbers. They come from every start month since 2006.
- Look at the chart. Each bar goes from the bad case to the good case.
- Compare the bars. A short bar means that the results were close together.
How this was calculated
At each start month, we took the 500 largest US companies by market value. Market value is the price of all the shares of a company.
We picked stocks from that list at random. Each stock got the same amount of money.
We did this 100 times for each start month, number of stocks and years held.
Dividends went back into the same stock. There was no trading after the start.
The results are before tax, fees and trading costs.
A company that left the market keeps its last price. A company that failed usually traded near zero at the end. So the effect is small, but it is not exact.
History starts in 2006. So there are fewer start months for 10 years held than for 1 year.
These are past results for learning. They are not investment advice.
Words on this page
Portfolio: a group of stocks that one person owns.
Made money: the share of portfolios that ended above the amount at the start.
Typical result: the middle result, also called the median. Half of the portfolios did better. Half did worse.
Bad case: the worst 5%. Only 5 in 100 portfolios did worse.
Good case: the best 5%. Only 5 in 100 portfolios did better.
Start month: the month when a portfolio was bought. Each month since 2006 is a start month.
MonkScore
How does your stock score?
MonkScore™ rates a company from 0 to 100 on five things at the same time. The scores are inside MonkStreet.
How this score is madeDisclaimer
- Growth (value available with a MonkStreet trial)
- Profitability (value available with a MonkStreet trial)
- Quality (value available with a MonkStreet trial)
- Conviction (value available with a MonkStreet trial)
- Safety (value available with a MonkStreet trial)
Questions
Diversified means that your money is spread over many stocks. Then one bad stock hurts the whole portfolio less. No single number is right for every person. The tool shows the range of past results for 1 to 50 stocks. A short bar means that the results were close together.
One stock can fall a lot or rise a lot. In the tool, choose 1 stock and read the bad case. Then compare it with 20 or 30 stocks. These are past results, not a promise.
In the tool, choose 1 year and then 10 years. Compare how many portfolios made money. Past results do not tell you what happens in the future.
It is the middle result, also called the median. Half of the portfolios did better. Half did worse.
At each start month since 2006, we took the 500 largest US companies. We picked stocks at random, with the same amount in each. Dividends went back into the same stock. We did this 100 times for each start month. The results are before tax and fees.
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