What sort of insanity is this? How could cash be an opportunity at a time when three-month T-bills yield less than 10 basis points? No one gets excited earning virtually nothing on their cash balances, but stock investors should consider future opportunities in addition to existing choices: It's not about what you're not earning on the cash today, it's about earning premium returns on the investments you'll be able to make with that cash tomorrow.

Cash needn't be an anchor
In the words of super-investor Seth Klarman: "Why should the immediate opportunity set be the only one considered, when tomorrow's may well be considerably more fertile than today's?" At the head of the Baupost Group, a multi-billion dollar investment partnership, Klarman employs a value-oriented strategy, achieving exceptional performance in spite of -- or rather, because of -- the fact that he frequently holds significant amounts of cash. For example, on October 31, 1999, a few months before the tech bubble began to collapse, his Baupost Fund was approximately one third in cash.

Over the "lost decade" spanning 1999 through 2008, Klarman smashed the market with a 15.9% average annualized return net of fees and incentives versus a (1.4%) annualized loss for the S&P 500.

Don't go all in (cash or equities)
Let me be quite clear: I'm not advocating that you liquidate all your stocks and go all into cash; the market's current valuation simply does not warrant that sort of drastic action. Conversely, it shouldn't compel you to raise your broad equity exposure, either.

As I noted last week, the market doesn't look cheap right now: Based on data compiled by Professor Robert Shiller of Yale, at yesterday's closing value of 1,071.66, the S&P 500 is valued at over 19 times its cyclically adjusted earnings, compared to a long-term historical average of 16.3. Based on average inflation-adjusted earnings, the cyclically adjusted P/E ratio is one of the only consistently useful market valuation indicators.

As prices increase, so does your risk
All other things equal, as share prices rise, stocks will represent a larger percentage of your assets; however, logic dictates you should actually seek to ratchet down your equity exposure under those circumstances. As stock prices rise, expected future returns decline (again, all other factors remaining constant), making stocks relatively less attractive. Another way to express this is that as stock prices increase, so does the risk associated with owning stocks.

That risk may simply be earning sub-par returns or, in the worst case, suffering capital losses. Extremes in market valuations offer the best illustration of this principle: Owning a basket of Nasdaq stocks in March 2000: a high-risk or low-risk strategy? How about buying Japanese stocks in December 1989, with the Nikkei Index nearing 39,000 (nearly 20 years on, the same index trades at less than 10,500).

Don't misinterpret Buffett's words
So what are we to make of Berkshire Hathaway (BRK-B) CEO Warren Buffett's words when he told CNBC on July 24th: "I would much rather own equities at 9,000 on the Dow than have a long investment in government bonds or a continuously rolling investment in short-term money"? (Investors must have concluded the same thing, sending the Dow 8% higher since then.)

First, with just 30 component stocks, the Dow isn't a broad-market index; it's a blue-chip index. The stocks of high-quality companies have underperformed the broader market in the rally from the March market low, which has left them relatively undervalued. This is reflected in the Dow's 14 price-to-earnings multiple, against 17 for the wider S&P 500.

Buying pieces of businesses vs. owning the market
Second, keep in mind that Buffett likes to own pieces of high-quality businesses, not the whole market. As I mentioned above, there is reason to believe that there is still opportunity left in the higher-quality segment of the market. The following table contains six companies that trade with a free-cash-flow yield above 10% -- i.e., they're priced at less than 10 times trailing free cash flow (these are not investment recommendations):

Company

Sector

Free-Cash-Flow Yield*

General Electric (NYSE:GE)

Conglomerates

47.3%

UnitedHealth Group (NYSE:UNH)

Health care

11.7%

Bristol-Myers Squibb (NYSE:BMY)

Health care

10.6%

Raytheon (NYSE:RTN)

Industrial goods

10.5%

Altria Group (NYSE:MO)

Consumer goods

11.5%

Time Warner (NYSE:TWX)

Services

25.9%

*Based on TTM free cash flow and closing stock prices on September 21, 2009.
Source: Capital IQ, a division of Standard & Poor's, Yahoo! Finance.

Summing up: What to do from here
To sum up: If, like Buffett, you have identified high-quality businesses that are undervalued, there is nothing wrong with buying them now. However, if you are mainly an index investor, it is probably ill-conceived to increase your exposure to stocks right now. Either way, whether you are a stockpicker or an index investor, there is nothing wrong with holding on to some cash right now -- not for its own sake -- but to take advantage of better stock prices at a later date.

Morgan Housel has identified three high-quality companies that are still cheap.

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Alex Dumortier, CFA, has no beneficial interest in any of the companies mentioned in this article. Berkshire Hathaway and UnitedHealth Group are Motley Fool Stock Advisor selections. Berkshire Hathaway and UnitedHealth Group are Motley Fool Inside Value recommendations. The Fool owns shares of Berkshire Hathaway and UnitedHealth Group. Try any of our Foolish newsletters today, free for 30 days. The Motley Fool has a disclosure policy.