Whether you're a beginning investor or a near-retiree, you can't overstate the importance of purchasing stocks that pay dividends. Not only do companies that have quarterly or annual payouts provide you with a steady stream of income, but they also hold the potential for capital appreciation. Simply put, dividend stocks can you give your portfolio what almost no other investment can -- both income and growth.

At The Motley Fool, we're avid fans of dividends -- and not just because we like that steady stream of cash. Studies have shown that from 1972 to 2006, stocks in the S&P 500 that didn't pay dividends earned an average annual return of 4.1%, while dividend stocks averaged a whopping 10.1% per year. That is an incredible difference -- one that you'd be crazy to not take advantage of!

But investing in dividends can be dangerous. Companies can cut, slash, or suspend dividends at any time, often without notice. Fortunately, there are several warning signs to look for, and any of them could be the crucial factor in determining whether a company is likely to continue paying its dividend. Today, let's drill down into Freeport-McMoRan Copper & Gold (NYSE: FCX).

What's on the surface?
Freeport-McMoRan Copper & Gold, which operates in the diversified metals and mining industry, currently pays a dividend of 1.54%. That yield may not seem like much, but considering that more than 100 companies in the S&P 500 don't pay anything at all, it's nothing to complain about. And don't forget that dividends typically grow with time, so that 1.54% has the potential to take off in a big way.

But what's more important than the dividend itself is Freeport-McMoRan Copper & Gold's ability to keep that cash rolling. The first thing to look at is the company's reported dividends versus its reported earnings. If you happen to see dividend payments that are growing faster than earnings per share, that may be an initial red flag. Check out the graph for details of the past five years:

Fcxdividendpershare

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

That big drop was due to more than $17 billion in goodwill and asset writedowns. Backing them out (after all, they weren't cash expenses) would reveal that the company still had enough cash coming in to pay the dividend. Of course, you don't want to see that kind of drop happening every year. In all, Freeport-McMoRan Copper & Gold has been able to boost its earnings at an adequate pace and keep its dividends in check at the same time.

The more secure, the better
One of the most common metrics that investors use to judge the safety of a dividend is the payout ratio. This number tells you what percentage of net income goes to investors in the form of a dividend. Normally, anything above 50% is cause to look a bit further. According to the most recent data, Freeport-McMoRan Copper & Gold's payout ratio is 9.26%. It's obvious that, at least on the surface, Freeport-McMoRan Copper & Gold doesn't face any trouble generating enough income to support that nice 1.54% dividend.

More important than checking out the payout ratio may be simply taking a peek at Freeport-McMoRan Copper & Gold's cash flow. Companies use free cash flow -- all the cash left over after subtracting capital expenditures -- to make acquisitions, develop new products, and, of course, pay dividends! We can use a simple metric called the cash-flow coverage ratio, which is cash flow per share divided by dividends per share. Normally, anything above 1.2 should make you feel comfortable; anything less, and you may have a problem on your hands. Freeport-McMoRan Copper & Gold's coverage ratio is 36.59, so it has more than enough cash on hand to keep pumping out that 1.54% yield. Barring any unforeseen circumstances, there shouldn't be any major problems moving forward.

Either way, it's always beneficial to compare an investment with its most immediate competitors. In the table below, I've included the above metrics with those of Freeport-McMoRan Copper & Gold's closest competitors. In addition, I've included the five-year dividend growth rate, which is also a very important indicator. If Freeport-McMoRan Copper & Gold can illustrate that it's grown dividends over the past five years, then there's a good chance it will continue to put shareholders first in the future. Check out how Freeport-McMoRan Copper & Gold stacks up:

Company

Dividend
Yield

Payout
Ratio

Coverage Ratio

5-Year Compounded Dividend Growth Rate

Freeport-McMoRan Copper & Gold

1.5%

9.3%

36.59

(20.6%)

Newmont Mining (NYSE: NEM)

1.0%

10.5%

10.33

1.3%

Southern Copper (NYSE: SCCO)

1.4%

71.9%

1.53

14.4%

Nucor (NYSE: NUE)

3.6%

297.7%

(0.13)

38.6%

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

The Foolish bottom line
In the end, only you can decide what numbers you're comfortable with. Sometimes a higher yield and a higher reward mean additional risk. However, when we look at Freeport-McMoRan Copper & Gold's payout ratio compared with its peer average, we see that it comes in at a lower percentage, and its dividend is therefore probably more sustainable. The bottom line is to make sure that with anything -- whether it be a dividend, a share repurchase, or an ordinary earnings report -- you do your own due diligence. Looking at all of the numbers in the best context possible is the best place to start.

Jordan DiPietro owns no shares of the stocks mentioned here. Nucor is a Motley Fool Stock Advisor selection. Try any of our Foolish newsletter services free for 30 days. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Motley Fool has a disclosure policy.