We'd all like to invest as successfully as the legendary Warren Buffett. He calculates return on invested capital 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 Coca-Cola (NYSE: KO) 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:

Company

TTM

1 year ago

3 years ago

5 years ago

Coca-Cola

22.5%

21.3%

18.7%

23.8%

Hansen Natural (Nasdaq: HANS)

60.5%

34.1%

77.4%

66.1%

PepsiCo (NYSE: PEP)

12.9%

21.1%

24.6%

21.5%

Source: Capital IQ, a division of Standard & Poor's.

While Coca-Cola has not shown steady gains in its return on capital, it has consistently produced returns of more than 18%, and often far beyond 20%. Its main rival in the cola wars, PepsiCo, has consistently produced a return on capital exceeding 12%, falling into the same ballpark. Pepsi's returns in the last year likely suffer from its recent acquisition of its bottlers, which are cash-intensive businesses. But I'd like to see its ROIC return to some of its former glory. Hansen has hit the ball out of the park, but its ROIC is down from the highest levels of a few years ago. Is the competition catching up?

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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