According to a Bank of America/Merrill Lynch report last year, growth stocks have returned an average of 12.6% annually since 1926. Rapid top- and bottom-line expansion is usually an allure for investors, but trying to find companies that can continue to grow at a market-topping pace beyond just a few years isn't so easy. 

With this in mind, we asked three of our Foolish investors for a growth stock that they believe has staying power beyond just the next couple of years. In fact, they believe these could be the growth stocks to own for the next 50 years. Topping their list were robotic-assisted surgical system developer Intuitive Surgical (NASDAQ:ISRG), benchmark and analytics provider S&P Global (NYSE:SPGI), and e-commerce behemoth Amazon.com (NASDAQ:AMZN)

A person holding binoculars and looking into the distance.

Image source: Getty Images.

A profit maker with surgical precision 

Sean Williams (Intuitive Surgical): Fifty years is a long time to set a growth stock and forget about it, but one name that's only primed to get stronger over time is robotic-assisted surgical system developer Intuitive Surgical.

It's no secret that Intuitive Surgical has been growing by a double-digit percentage for a very long time. Its range of da Vinci surgical systems assist surgeons with various soft-tissue procedures, helping to minimize incision size and healing time for the patient. Currently a mainstay in gynecology and urology surgery, the company is aiming to ramp up its use in thoracic and colorectal surgery in the years to come.

While procedural expansion in regard to new indications is exciting for the company and investors, this isn't necessarily its major source of growth over the long run. Selling its da Vinci systems for $0.6 million to $2.5 million isn't a big deal, either. You see, these machines are costly and time-consuming to develop, so they're generally a low-margin item.

The real money comes from the instrument-per-procedure revenue and the annual service calls derived from its growing installed base. Instrument and service revenue is high margin, and as the installed base of da Vinci systems increases, the percentage of high-margin sales as a percentage of revenue derived from da Vinci surgical system sales should grow, pushing its operating margins higher at a quicker pace than total sales growth. 

Furthermore, with more installed robotic-assisted machines than any of its competitors combined by a mile, it essentially locks hospitals and universities that've bought Intuitive Surgical's machines in for an extended period of time. It takes time and money to train surgeons on how to use the da Vinci surgical system, meaning there's a rapport that the company's builds with the medical community that its peers probably won't be able to hold a candle to.

Added together, we've got an aging population that should lend to an increase in procedure volume over time, an expanding base of installed systems, a pathway to margin expansion, and clear competitive advantages in the industry.

A businessman holding a stopwatch behind an ascending stack of coins.

Image source: Getty Images.

A true cash cow

Jordan Wathen (S&P Global): Get three businesses under one umbrella. S&P Global generates revenue from its debt ratings, market intelligence, and S&P Dow Jones Indices businesses, which together form the basis of this highly profitable company.

Debt ratings are its bread and butter. Last quarter, the company generated $739 million in revenue from ratings, earning a 51% operating profit margin. S&P Global essentially acts as a royalty on debt issuance, as the company earns a small fee on every bond it rates.

Likewise, the S&P Dow Jones Indices unit is extraordinarily profitable, primarily due to licensing fees it earns from funds that track one of its indexes. Last quarter, the unit generated operating profit of $119 million on just $187 million of revenue for an astounding 64% operating profit margin.

Over the long term, I think S&P Global can grow operating profit at a high single-digit clip while returning the bulk of its earnings power back to shareholders in the form of dividends and repurchases. Growth won't come in a straight line, as its profit rises or falls with global debt issuance and index fund flows, but it's my view that investors who buy and hold for the long haul can earn a market-beating return from this extraordinary business.

An Amazon logistics employee packing merchandise for a customer.

Image source: Amazon.com.

Primed for big growth

Keith Noonan (Amazon): How long can Amazon continue to deliver stellar growth and stock returns? That's been a popular point of contention for well over a decade and one that's especially relevant with shares at record highs, but I think the company looks primed to continue delivering wins over the long term. The strength of its online retail and cloud services businesses and its early leadership in many of the most important tech trends on the horizon make it a stock that's worth holding for the next half-century. 

Amazon's web store is still growing at a rapid clip, with sales up roughly 28% last quarter, and its outlook remains promising. For the June-ended quarter, the U.S. Department of Commerce reported that e-commerce accounted for just 8.9% of total retail sales. That leaves Amazon a lot of room for growth, particularly as its Prime membership program continues evolving to keep customers wrapped up in the company's ecosystem. Amazon's expansion in international markets is still ramping up as well. The web giant's most recent quarterly report saw its international segment grow 29% to account for roughly 36% of its online store sales. 

Amazon Web Services also looks poised to retain a leadership position in the cloud infrastructure space, and the platform gives the company a hugely profitable business that dovetails with game-changing technologies like artificial intelligence. Amazon has come a long way from its beginnings as an online book store, and its sturdy core businesses and penchant for innovation suggest it will continue to be one of the world's most influential companies over the next 50 years and beyond.

John Mackey, CEO of Whole Foods Market, an Amazon subsidiary, is a member of The Motley Fool's board of directors. Jordan Wathen has no position in any of the stocks mentioned. Keith Noonan has no position in any of the stocks mentioned. Sean Williams owns shares of Bank of America. The Motley Fool owns shares of and recommends Amazon and Intuitive Surgical. The Motley Fool has a disclosure policy.