The Anatomy of a Lost Decade


What leads to lost decades? (There may be multiple answers.)

  1. Wars.
  2. Pandemics.
  3. High valuations, as measured by price/book or price/earnings.
  4. Extreme economic distress.
  5. Euphoria.

The Anatomy of a Lost Decade

In the 2000’s, the S&P 500 experienced a 10-year decline, on a total return basis (including dividends), and much worse after counting the negative effect of inflation. This was not the first time – the decade ending in 1974 had +1.2% return per year, while inflation averaged 5.2% per year. This article describes what may lead to such long declines, and how they look.

What led to lost decades? A diversified portfolio of companies that produces products and services for entire countries is not likely to shrink its production for 10 years. What led to the 2 recent lost decades was high valuations (high price relative to the earnings of the companies or book values) of the companies. During the decade, the valuations declined by more than 50%, to correct (and typically overcorrect) the unusual pricing.

How did they look? The two most recent lost decades involved a series of gain periods followed by big declines, erasing substantial gains.

Can you avoid lost decades? There is no way to perfectly time the market, since turning points vary between cycles, with highs sometimes (but not always) leading to higher levels. There are various approaches with varying levels of success, involving getting out of diversified investments that did far above average for 10 years, or selling when valuations reach extremes. The easiest one is to diversify and include investments with lower average growth. While it involves a sacrifice to the returns, it gets around so many strategies that fail.

Why most people fail at timing? Once you find a strategy that stood the test of time, and has sound logic to it, you still have a major obstacle to overcome. Selling high and buying low involves going against the grain. It involves selling the most loved investment of the time, that people believe will just keep going up, and buying battered investments that underperformed for many years.

Can you avoid lost decades? While it is very difficult to time the market, or at least soften the blow of tough stretches, there are several principles that can improve your odds:

  1. When you hear gloomy news, along with scary predictions, and the investments are very low (low valuations / low 10 year returns), get excited about the investment.
  2. When you see euphoria all around you, with the most positive news, and the investments are sky high (high valuations / high 10 year returns), have the ability pull the trigger and sell and switch to an investment that most people hate.
  3. Whatever strategy you choose, make sure that it passed 2 tests: the test of time & the test of logic. While these are not enough, I would not move forward without these in place.
  4. Don’t expect to successfully time within one day, week, month or even year. Short-term timing strategies are far more difficult than long-term ones.
  5. Have a very robust risk plan, accounting for cases much worse than experienced in the past, allowing you to stick with the plan in some of the toughest times.

Quiz Answer:

What leads to lost decades? (There may be multiple answers.)

  1. Wars.
  2. Pandemics.
  3. High valuations, as measured by price/book or price/earnings. [Correct Answer]
  4. Extreme economic distress.
  5. Euphoria. [Correct Answer]


  1. Wars end up leading to increased economic activity. Declines tend to be far shorter than a decade.
  2. Pandemics tended to create short-term shocks, not very long lasting.
  3. High valuations typically get corrected. When valuations reach extremes, such as x2 the typical or more, it takes a prolonged period of poor performance to correct those.
  4. Extreme economic distress can lead to declines, but without high valuations, they tend to get resolved in far less than 10 years.
  5. Euphoria tends to lead to very high valuations – see #3 above.
Disclosures Including Backtested Performance Data