Over the past six-plus weeks, investors have taken quite the beating, and their resolve to stay invested has been tested like never before.

The spread of the coronavirus disease 2019 (COVID-19) pushed equities into bear market territory in just over three weeks, and they're down 30% in a mere 22 trading sessions (about a month). Both represent the steepest descents from a recent high for the broader market in its storied history and are indicative of the unprecedented mitigation measures being undertaken -- and the resulting economic damage we're bound to see -- to slow the spread of COVID-19.

A person planting one hundred dollar bills in the ground.

Image source: Getty Images.

Yet every bear market in history has had one thing in common: They've always been buying opportunities. If you seek out high-quality businesses and hold onto them for long periods of time, history says you should make money.

The thing is, you don't always have to choose value stocks to invest in during a bear market. With lending rates moving back to historic lows and the Federal Reserve pledging an unlimited amount of quantitative easing to buoy the U.S. economy, the stage is set for high-growth companies to thrive for the foreseeable future. (Note, I'm arbitrarily defining "high-growth" as a company with a sustainable growth rate of at least 10% per year.)

If you're an investor with, say, $2,500 in disposable income -- i.e., cash that you don't need to pay bills or for emergencies -- then now is the time to consider putting that money to work by purchasing these five high-growth stocks.

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Image source: Facebook.

Facebook

While there's a good likelihood that social media giant Facebook (NASDAQ:FB) is going to deal with negative short-term repercussions from COVID-19 since its business is predominantly dependent on advertising, Wall Street is overlooking the company's countless competitive advantages.

For one, where else can advertisers go to get access to 2.5 billion monthly active users or 1.66 billion daily active users (DAUs)? The answer, in case you're wondering, is nowhere. Facebook holds incredible pricing power given its advantageous position as social media's most-popular platform, and it translated that pricing power into 25% ad-revenue growth in 2019, despite "just" 9% DAU growth year over year. 

What's more, Facebook hasn't even begun to monetize WhatsApp or Facebook Messenger, which along with Instagram and Facebook represent four of the seven most-visited social media platforms. Facebook's cash flow is set to soar in the years ahead if it monetizes WhatsApp and organically grows its existing revenue-generating platforms. Look for sales growth to remain in the 15% to 20% range per year.

A surgeon holding a one dollar bill with surgical forceps.

Image source: Getty Images.

Intuitive Surgical

Surgical-assisted robotics company Intuitive Surgical (NASDAQ:ISRG) is arguably my top investment idea for April. Even though it'll see some weakness from a very near-term reduction in elective procedures, its numerous moats will shine through over the long term.

For example, Intuitive Surgical finished 2019 with close to 5,600 of its da Vinci surgical systems installed around the world. You could add up every one of Intuitive's competitors and wouldn't come close to its installed base. Given the price of these systems ($0.5 million to $2.5 million) and the training given to surgeons, there's also virtually no chance of client churn. Or in layman's terms, these hospitals and surgical centers become customers for life. 

Intuitive Surgical is also built on the razor-and-blades business model. Clients buy the razor, which in this case is the pricey da Vinci system, then purchase instruments and accessories with each procedure, as well as pay for servicing to keep these machines in tip-top shape. The razor is generally a low-margin item, but the instruments and service segments are both high margin. As the company's base of systems grows, so does the company's margins -- it's that simple.

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Image source: Getty Images.

Palo Alto Networks

The coronavirus crash has been fairly indiscriminate with regard to the stocks it wallops, and cybersecurity company Palo Alto Networks (NYSE:PANW) is no exception. The possibility of slower product orders and supply-chain disruptions and the fact that Palo Alto already admitted to higher expenditures in 2020 before COVID-19 became a serious issue have all worked against this stock recently.

But look at this from another angle: Cybersecurity isn't exactly something that's elective. Enterprise customers absolutely need their internal and cloud systems protected from sophisticated hacking attempts, and Palo Alto provides these services. Thus, no matter how dreary the forecast might seem, Palo Alto is providing what's essentially a basic-need service for businesses in any economic environment.

Furthermore, Palo Alto has been focusing its attention on bolstering its higher-margin cloud-protection services and is generating a greater percentage of its revenue from subscriptions. Not only are subscriptions a higher-margin source of sales, but they're also far more predictable than product sales. Look for Palo Alto to continue growing its top-line sales by 15% to 20% per year.

An up-close view of a flowering cannabis plant growing in an indoor cultivation farm.

Image source: Getty Images.

Innovative Industrial Properties

At this time last year, virtually nothing could stop the red-hot marijuana industry. But nowadays, practically all pot stocks are hanging on by a thread. I say "practically," because cannabis real estate investment trust Innovative Industrial Properties (NYSE:IIPR) has been "kicking bud" and taking names.

To date, Innovative Industrial Properties has acquired 53 cultivation and processing assets in 15 states, with a weighted-average lease length of 15.9 years and an average return on invested capital of 13.2%. In simple terms, this means IIP should net a complete payback on its investments in roughly 5.5 years but continue to generate rental income for about three times that long, all with relatively low fixed costs.

Innovative Industrial Properties is also benefiting from the fact that cannabis remains federally illegal in the United States. Since U.S. multistate operators are struggling to gain access to non-dilutive financing, IIP has stepped in as a source of financing via sale-leaseback agreements. With neither Republican incumbent Donald Trump nor probable Democratic Party nominee Joe Biden likely to alter marijuana's classification if elected in November 2020, IIP should hang onto this advantage for years to come.

An Amazon employee speaking with a woman who is outside his Prime-labeled van.

Image source: Amazon.

Amazon

I'm sure you're probably tired of me beating the dead horse on Amazon (NASDAQ:AMZN) of late, but there's not a service-oriented company in a better position to see its cash flow soar in the years to come.

Amazon has quietly dazzled Wall Street for more than two decades with its growing e-commerce presence and more recently with its Prime membership. The company now has more than 150 million Prime members worldwide, which not only helps to keep users loyal to the Amazon ecosystem of products, but also helps to boost generally anemic retail margins.

However, the real allure here is the company's cloud-based operations, Amazon Web Services (AWS). Cloud-service margins are light year's higher than retail margins, so as AWS grows into a larger percentage of total sales, Amazon should see its cash flow grow considerably faster. Perhaps this explains Wall Street's expectation of a near-tripling in cash flow between 2019 and 2023 for the company.

Despite its already large market cap, Amazon has plenty of room left to run higher.