Does Amgen Pass Buffett's Test?

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 are from 8% to 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 Amgen (Nasdaq: AMGN) 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:

Source: Capital IQ, a division of Standard & Poor's. TTM = trailing 12 months.

Amgen has consistently produced returns on capital above 12%, and shows the type of steady growth that we like to see, suggesting the ongoing strength of its competitive position. Sanofi, on the other hand, fails to meet our 12% threshold for attractiveness but has also shown fairly steady growth in the past five years. Novartis fills the middle with the attractive margins of a big pharma company, and seems to have a defensible moat.

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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