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, Casey's General Stores (Nasdaq: CASY).                 

Casey's General Stores shares have easily outperformed the S&P 500 over the last quarter-century, with most of the outperformance occurring in the last few years:

Casysp

Source: S&P Capital IQ.

Since 1987, shares have returned an average of 12.3% 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 Casey's General Stores, it'd be worth $41,000.  

Dividends accounted for a lot of those gains. Compounded since 1987, dividends have made up 17% of Casey's General Stores' total returns. For the S&P, dividends account for 39% of total returns.

Now have a look at how Casey's General Stores earnings compare with S&P 500 earnings:

Casyearnings

Source: S&P Capital IQ.

Pretty good outperformance. Since 1995, Casey's General Stores earnings per share have increased by 11.8% per year, compared with 6% a year for the broader index.

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

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