Based on the aggregated intelligence of 170,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, railroad giant Union Pacific (NYSE: UNP) has earned a respected four-star ranking.

With that in mind, let's take a closer look at Union Pacific's business and see what CAPS investors are saying about the stock right now.

Union Pacific facts

Headquarters (founded) Omaha, Neb. (1862)
Market Cap $43.84 billion
Industry Railroads
Trailing-12-Month Revenue $16.31 billion
Management

CEO James Young (since 2005)

CFO Robert Knight Jr. (since 2004)

Return on Equity (average, past 3 years) 13.8%
Cash/Debt $1.36 billion / $9.72 billion
Dividend Yield 1.5%
Competitors

Canadian National Railway (NYSE: CNI)

CSX (NYSE: CSX)

Norfolk Southern (NYSE: NSC)

Sources: Capital IQ (a division of Standard & Poor's) and Motley Fool CAPS.

On CAPS, 97% of the 1,134 members who have rated Union Pacific believe the stock will outperform the S&P 500 going forward. These bulls include IRVINGP and flowmaster5.

This past summer, IRVINGP tapped Union Pacific as a great way to stay on track: "Growth in export of raw materials and imports of finished goods coupled with the fuel economy of rail transportation will drive Union Pacific stock higher as the US economy recovers."

As North America's largest railroad, Union Pacific remains one of our community's favorite ways to play an economic turnaround. While Union Pacific's profitability has historically been close to the bottom of the industry, management has led some impressive margin expansion over the past few years. Of course, with plenty of room for improvement still left, Union Pacific's paltry PEG ratio of 0.9 -- a discount to fellow railways Canadian National (1.3), CSX (1.2), Norfolk (1.3), and Kansas City Southern (NYSE: KSU) (1.2) -- may be too attractive to pass up.

CAPS member flowmaster5 sums up the bull case:

According to a September report from American Association of Railroads, traffic is broadly up. Add to this the feel good momentum to keep as much traffic as possible off the roads, and the relative fuel efficiency of railroad transport, and [Union Pacific] is positioned to outperform for some time to come. Railroad is a big part of the green revolution moving forward!

What do you think about Union Pacific, or any other stock for that matter? If you want to retire rich, you need to put together the best portfolio you can. Owning exceptional stocks is a surefire way to secure your financial future, and on Motley Fool CAPS, thousands of investors are working every day to find them. CAPS is 100% free, so get started!

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Canadian National Railway is a Motley Fool Stock Advisor pick. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Fool's disclosure policy always gets a perfect score.