As investors, we need to understand how our companies truly make their money. A neat trick developed for just that purpose -- the DuPont Formula -- can help us do so.

The DuPont Formula can give you a better grasp on exactly where your company is producing its profit, and where it might have a competitive advantage. Named after the company where it was pioneered, the formula breaks down return on equity into three components:

Return on equity = net margin X asset turnover X leverage ratio

What makes each of these components important?

  • High net margins show that a company can get customers to pay more for its products. Luxury-goods companies provide a great example here.
  • High asset turnover indicates that a company needs to invest less of its capital, since it uses its assets more efficiently to generate sales. Service industries, for instance, often lack big capital investments.
  • Finally, the leverage ratio shows how much the company is relying on liabilities to create its profits.

Generally, the higher these numbers, the better. But too much debt can sink a company, so beware of companies with very high leverage ratios.

Let's see what the DuPont Formula can tell us about General Dynamics (NYSE: GD) and a few of its sector and industry peers.

Company

Return on Equity

Net Margin

Asset Turnover

Leverage Ratio

General Dynamics 19.7% 8.3% 0.99 2.39
Textron (NYSE: TXT) 10.2% 2.9% 0.71 4.97
Harris (NYSE: HRS) 24.4% 9.1% 1.05 2.54
Northrop Grumman (NYSE: NOC) 15.7% 5.8% 1.21 2.20

Source: S&P Capital IQ.

The asset turnover here is in a fairly narrow range, as is leverage, with the exception of Textron. So the major differences in ROE are largely determined by differences in net margin. General Dynamics puts up the second-best margin and turns in the second-best ROE, which is topped by Harris and its higher margin. Northrop's lower margin lands it in third, while Textron uses higher leverage to offset lower asset turnover and margin.

Using the DuPont formula can often give you some insight into how a company is competing against peers and what type of strategy it's using to juice return on equity. To find more successful investments, dig deeper than the earnings headlines.

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