Entering text into the input field will update the search result below

The Overall Stock Market Is Not In A Bubble

Please Note: Blog posts are not selected, edited or screened by Seeking Alpha editors.

Dividend Investing

Seeking Alpha Analyst Since 2008

Individual value investor with strong penchant for dividend growth.  A former tax and estates attorney who retired in his early 40s and expatriated to Lisbon, Portugal with his family. Now writes about tax law, portfolio strategy and life in sunny Portugal and tutors students in personal financial planning.

Association with SA author Evelyn Trias

Contributor, CNBC

Producer of "The Quarterly Compounder" channel on YouTube.com.


  • At first glance, the price/ earnings ratio for the S&P 100 looks very high and supports the idea that the market is in bubble territory.
  • The reason why the PE ratio for the S&P 100 appears high is because 12% of the index is weighted into just four stocks with unusually high PE ratios.
  • Take out these four statistical outliers and the overall valuation of the S&P 100 looks much cheaper.

I recently read an article here on SeekingAlpha that argues we are in an historic bubble and that investors should sell all their stocks and bonds and hold cash and commodities for the next seven years. The premise for this rather alarming course of action assumes that we are, in fact, in a bubble. So are we?

To try to answer that question, I looked at the 100 holdings of the Ishares S&P 100 ETF (OEF), took the PE ratio for each holding (using Googlefinance as the data source), and took the weighting of each position according to the IShares homepage. I then screened out any PE ratios that are zero or less. Next, I checked the PE ratios from Googlefinance against those I found on SeekingAlpha. For example, Googlefinance retrieves a PE ratio of 1684 for Tesla (TSLA). I swapped that out for the SeekingAlpha reported PE ratio of 343. After double checking the data, I then generated an overall weighted average PE ratio for the entire S&P 100 of 48.  

Squarely in bubble territory. 

But you have to dig deeper. Look what happens if you screen out JUST ONE STOCK from the S&P 100.  (TSLA) comprises over 3% of the S&P 100 according to Ishares and has a PE ratio that is dramatically outside the bell curve of PE ratios for stocks in the S&P 100. I removed that one single statistical outlier and re-weighted 3% of the portfolio using the resulting average PE ratio, and found that the overall weighted average PE ratio for the whole S&P 100 drops precipitously to 38.5.

Amazing how just one stock can so extremely skew the average PE ratio for the entire index.

But in fact, the S&P 100 is weighted towards a few other statistical outliers with PE ratios that Googlefinance reports at close to 100 (over two times the index average).  Amazon (AMZN) currently comprises over 6% of the entire S&P 100, (NVDA) comprises 1.5%, and Disney (DIS) comprises another 1.5%. Take out those other three statistical outliers and the PE ratio for the entire S&P 100 drops down to a far cheaper level of 32.  That tells a radically different story than an index with an average PE ratio of 48.


You can't infer that the whole market is in a bubble until you look at the impact of statistical outliers on the overall average PE ratio for the index. 4 companies in the S&P 100 may very well be trading in extreme bubble territory, which disguises the fact that the remaining 96 companies in the index aren’t. Here is a link to the data

Analyst's Disclosure: I am/we are long AMZN.

I am not an investment advisor and this is not investment advice. I cannot guarantee the accuracy of any computation or any data source that I relied on when I did the calculations.

Seeking Alpha's Disclosure: Past performance is no guarantee of future results. No recommendation or advice is being given as to whether any investment is suitable for a particular investor. Any views or opinions expressed above may not reflect those of Seeking Alpha as a whole. Seeking Alpha is not a licensed securities dealer, broker or US investment adviser or investment bank. Our analysts are third party authors that include both professional investors and individual investors who may not be licensed or certified by any institute or regulatory body.

Recommended For You

To ensure this doesn’t happen in the future, please enable Javascript and cookies in your browser.
Is this happening to you frequently? Please report it on our feedback forum.
If you have an ad-blocker enabled you may be blocked from proceeding. Please disable your ad-blocker and refresh.