Over the past month, I dug into Bank of the Ozarks (NASDAQ:OZK). Along the way, I created a dozen or so charts.

Two of those charts perfectly capture why the biggest bank in Arkansas has caught many an investor's eye.

Total return since going public

Since going public in 1997, Bank of the Ozarks has generated a total shareholder return of more than 5,000%.

No other bank comes even close:

A bar chart comparing the returns of banks with more than $5 billion in assets.

Includes banks on the KBW regional and big bank indexes that have generated a positive return over the past 20 years. Data source: S&P Global Market Intelligence. Chart by author.

And it's not as if Bank of the Ozarks hasn't been up against stiff competition.

There's M&T Bank (NYSE:MTB), run by the Buffett of banking, Robert Wilmers. And Wells Fargo (NYSE:WFC), which, despite its issues, has created a lot of value for shareholders through the years. And U.S. Bancorp (NYSE:USB), the most consistently high-performing bank since before the financial crisis.

And many others.

The point is that Bank of the Ozarks' total return over the past 20 years doesn't just loom over a bunch of random banks; it looms over the best in the business.

Rapid organic loan growth

Bank of the Ozarks has accomplished this by growing incredibly fast. It has quintupled in size and generated two-thirds of its total return over the past five years alone.

As you can see in the chart below, the growth of its loan book has been off the charts:

A line chart comparing the growth in Bank of the Ozarks' loans to all other banks.

All banks includes all institutions insured by the FDIC. Data source: FDIC's Statistics on Depository Institutions. Chart by author.

Some of this is from acquisitions, but most of it is from Bank of the Ozarks' organic growth strategy.

The bank's loan growth started to lift off from the industry at large in 2003. That was the year Bank of the Ozarks opened its real estate specialties group, or RESG, to make large and complex commercial real estate loans.

A decade later, the growth rate dramatically accelerated following 2012, the year RESG president, Dan Thomas, became chief lending officer of the bank.

Since then, RESG has broadened its horizons, lending money on large construction and development projects in most major metropolitan areas across the country.

That includes New York City, Chicago, Philadelphia, Miami, and just about every other one of the 20 biggest metropolitan areas in the country, as well as many smaller ones.

A map with a red pin stuck in Little Rock, Arkansas.

Bank of the Ozarks doesn't let geography stand in the way of loan growth. Image source: Getty Images.

Out-of-market lending like this is notoriously risky. But it can also be lucrative, as Bank of the Ozarks' stock performance demonstrates.

To this end, two-thirds of its 20-year total return has come since 2012, the year Thomas was promoted to chief lending officer.

The Bank of the Ozarks story

The Bank of the Ozarks story is a fascinating one for anyone with an interest in banking or bank stocks.

Over the coming weeks and months, I'll be digging into it with short pieces like this. I encourage you to follow along.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.