With the S&P 500 still down more than 30% since the start of 2008, many wary investors have been turning to the safety of dividend-paying stocks.

In just the last three months of '08, for example, domestic dividend-focused ETFs that invest in high-yielders experienced net inflows of $1 billion.

Buyer beware
While dividends provide a source of income that helps to smooth out market volatility, crises like the present one are leaving many companies with little choice but to reduce or omit payments. According to data from Capital IQ, some 370 companies cut their dividends last year, and their stock prices had an average return of negative 56% for the year.

While in 2009 there are still companies like Altria (NYSE: MO), Best Buy (NYSE: BBY), and Boeing (NYSE: BA) that continue raising their payouts, we've already broken the record set in 2008 for most skipped payments in one year, at over $46 billion. Pfizer (NYSE: PFE) and Black & Decker (NYSE: BDK) are just some of the latest victims.

So how can you tell if your company is about to make a cut? In January, I argued that Dow Chemical and Huaneng Power were risking dividend cuts. (Both have since done so.) Among the warning signs these companies exhibited:

  • High yields
  • High payout ratios
  • Industry headwinds

Extremely high yields signal investors' skepticism that the company will be able to maintain its dividend. When National City announced its first dividend cut last year, for example, the stock was "yielding" 10%. Since then, the stock plunged, and the company was acquired by PNC. A high payout ratio -- particularly when combined with a difficult operating environment -- suggests that the company doesn't have enough free cash flow to support its payouts.

But these factors don't necessarily imply that a cut is imminent. Many other companies have continued to pay dividends they cannot afford for years, damaging their own firms -- and the value of your shares -- in the process.

I'll spare you all the details
A fascinating 2004 survey explains how and why. A team of four professors from Duke and Cornell surveyed more than 400 financial executives, discovering that 94% of executives "strongly ... or very strongly ... agree that they try to avoid reducing dividends." Many admitted to selling assets, laying off employees, borrowing heavily, or omitting important projects before cutting dividends.

See, these managers know that the market reacts negatively to dividend cuts. Several executives noted that Wall Street's response is an especially important consideration during liquidity crises -- such as the present one -- because they wouldn't want lenders to think their company is struggling.

But let's get back to payout ratios. Unfortunately, if a company isn't generating enough free cash flow to support its payout, the extra cash has to come from someplace else. Aside from raising revenue or cutting expenditures, there are four basic ways a company can collect the cash it needs to make such payouts:

  • Burn existing cash reserves
  • Borrow money
  • Issue shares
  • Sell assets

And while some of these practices may be acceptable bandage for a difficult year, none is sustainable over the long term. A company that pursues these strategies for too long will eventually burn itself out, damaging its shareholders in the process. Even worse, it's likely that it will ultimately have to cut its dividend anyway.

So which companies might fit that description today?

Two companies risking a burnout
These two companies have paid out more in dividends than they took in as free cash flow (or were free-cash-flow negative) over the past three years:

Company

Net Income Payout Ratio

Free Cash Flow Payout Ratio

Total 3-Year Shortfall*

Funding Method

American Capital

N/A

96%

$308 million

Stock, debt, sell assets

Vector Group (NYSE: VGR)

696%

117%

$40 million

Debt

Data from Capital IQ, a division of Standard & Poor's.
*Calculated as total dividends paid minus free cash flow.

As a Regulated Investment Company, American Capital is required to pay out 90% of its taxable income in the form of dividends. For the past few years, the company could afford to do so by diluting shareholders and issuing debt (and, last year, selling investments).

Annualizing the most recent distribution shows the stock yielding more than 130%. But investors should be aware that it could become more difficult to support the dividend in the future. That's because the private equity firm's cost of capital is rising due to a recent credit downgrade and more than $4 billion worth of debt.

Vector Group's dividend is in far better shape than a simple net income payout ratio would suggest, but the maker of Liggett Select and Grand Prix cigarettes pays out more cash than it brings in.

The silver lining ...
Dividend stocks have a history of putting money in investors' pockets, but choosing the right dividend stocks for a down market is critical to protecting your portfolio. Paying close attention to how your company funds its dividend will help you achieve the golden returns dividends offer.

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This article was originally published on March 26, 2009 under the headline "The Next 3 Dividend Burnouts?" It has been updated.

Ilan Moscovitz is neither long nor short any companies mentioned in this article. Best Buy and Pfizer are Inside Value selections. Best Buy is also a Motley Fool Stock Advisor recommendation and Fool holding. Huaneng Power is both a Rule Breakers and an Income Investor pick. The Fool has a disclosure policy.