We'd all like to invest as successfully as the legendary Warren Buffett. He calculates return on invested capital (ROIC) to help determine whether a company has an economic moat -- the ability to earn returns on its money beyond that money's cost.

ROIC is perhaps the most important metric in value investing. By determining a company's ROIC, you can see how well it's using the cash you entrust to it, and whether it's actually creating value for you. Simply put, ROIC divides a company's operating profit by the amount of investment it took to get that profit:

ROIC = Net operating profit after taxes / Invested capital

This one-size-fits-all calculation cuts out many of the legal accounting tricks (such as excessive debt) that managers use to boost earnings numbers, and provides you with an apples-to-apples way to evaluate businesses, even across industries. The higher the ROIC, the more efficiently the company uses capital.

Ultimately, we're looking for companies that can invest their money at rates that are higher than the cost of capital, which for most businesses lands between 8% and 12%. Ideally, we want to see ROIC greater than 12%, at minimum. We're also seeking a history of increasing returns, or at least steady returns, which indicate that the company's moat can withstand competitors' assaults.

Let's look at AT&T (NYSE: T) and two of its industry peers to see how efficiently they use capital. Here are the ROIC figures for each company over several time periods:



1 year ago

3 years ago

5 years ago






Verizon Communications (NYSE: VZ)





Sprint Nextel (NYSE: S)





Source: Capital IQ, a division of Standard & Poor's. *The company reported a net loss for the period.

Telecom companies usually require a huge amount of fixed assets to compete effectively, so it shouldn't be a huge surprise to see these carriers reporting lackluster ROIC numbers. AT&T has consistently failed to meet our 12% threshold for attractiveness. While Verizon Communications has also failed in that regard, it has produced the kind of steady increases that we like to see. Sprint Nextel isn't even close, having bounced in and out of profitability over the last half-decade.

It should be noted that disparities in tax rates among these companies significantly alter these results. In the TTM periods, for example, AT&T had an effective tax rate of 37.4%, while Verizon’s rate came in at a much lower 15.0%. That disparity is relatively consistent over the last few years. So Verizon’s relative outperformance relies heavily on the difference in tax rates, a factor that is less than encouraging.

Businesses with consistently high ROIC are efficiently using capital. They can use their extra returns to buy back shares, further invest in their future success, or pay dividends to shareholders. (Warren Buffett especially likes that last part.)

To unearth more successful investments, dig a little deeper than the earnings headlines, and check up on your companies' ROIC.

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