Investing isn't easy. Even Warren Buffett counsels that most investors should invest in a low-cost index like the S&P 500. That way, "you'll be buying into a wonderful industry, which in effect is all of American industry," he says.

But there are, of course, companies whose long-term fortunes differ substantially from the index. In this series, we look at how individual stocks have performed against the broad S&P 500. 

Step on up, Royal Gold (Nasdaq: RGLD).                                         

Royal Gold shares have easily outperformed the S&P 500 over the past quarter-century, with most of the outperformance occurring in the last few years:

Rgld

Source: S&P Capital IQ.

Since 1987, shares have returned an average of 14.4% a year, compared with 9.7% a year for the S&P (both include dividends). That difference adds up fast. One thousand dollars invested in the S&P in 1987 would be worth $19,200 today. In Royal Gold, it'd be worth $74,700.  

Dividends accounted for a lot of those gains. Compounded since 1987, dividends have made up about 15% of Royal Gold's total returns. For the S&P, dividends account for 39% of total returns.

Now have a look at how Royal Gold earnings compare with S&P 500 earnings:

Rgld

Source: S&P Capital IQ.

Pretty good outperformance. Since 1995, Royal Gold earnings per share have increased by 15.6% per year, compared with 6% a year for the broader index. 

Through it all, shares have been strong performers over the past quarter-century.  

Of course, the important question is whether that will continue. That's where you come in. Our CAPS community currently ranks Royal Gold with a three-star rating (out of five). Care to disagree? Leave your thoughts in the comment section below, or add Royal Gold to My Watchlist.