2021 was a tough year for many growth-stock investors. Between market sentiment switching to "economic reopening" plays and many internet and cloud-computing businesses lapping tough comparisons from 2020 (when digital services were seemingly our only link to the outside world during lockdowns), many growth stocks finished the year down by double-digit percentages.

Anaplan (PLAN), Magnite (MGNI -2.20%), and Appian (APPN -1.98%) were in that list of falling growth stocks, with their stock prices down 36%, 43%, and 60%, respectively, in 2021. Nevertheless, all three companies are still growing and are poised for a rebound in 2022 and beyond. Here's why.

Three people in an office looking at a computer.

Image source: Getty Images.

1. Anaplan: Using machine learning to make better organizational decisions

Connected resource planning is more important than ever these days. Between the rapid adoption of cloud-computing software and ongoing business disruption from the pandemic, organizations are in need of software that can help them make intelligent decisions and plan for the future.

That's where enterprise resource planning firm Anaplan comes in. The company's platform uses machine learning software that can be deployed throughout a company's operations to help teams make more accurate decisions and allocate resources to the right place. Software like this took a back seat in 2020, as many of Anaplan's customers were in damage-control mode, but sales have been picking up steam again. Anaplan grew total revenue at a 35% clip year over year in Q3 fiscal 2022 (the three months ended Oct. 31, 2021), up from a 28% growth rate a year ago.

The stock took a beating last year as high-growth but richly valued stocks fell out of favor with investors. However, the resource planning market is huge, and Anaplan is still a small player with an enterprise value of just $6.5 billion -- valuing the stock at just over 11 times current-year sales to enterprise value. Armed with more than $312 million in cash and equivalents and no debt, Anaplan can continue its aggressive marketing campaign to promote growth.

Given that Anaplan intentionally operates at a small loss each quarter, expect this stock to remain volatile in the new year. Nevertheless, with cloud computing still on the rise, this company will find plenty of opportunities to expand in the years ahead as it promotes its next-gen software services. If it can maintain its double-digit percentage revenue momentum, shares could be poised for a jump higher in 2022.

2. Magnite: A leader in connected-TV advertising

Magnite is a leader in sell-side digital connected-TV (CTV) advertising, which means it works with publishers to sell ad time on their video content. By way of a few acquisitions, Magnite is a top name in this CTV space, a lucrative niche to be in as television transitions toward internet-based streaming services.

This migration to more modern delivery of video content will take years to play out, and Magnite thus issued a rosy outlook for shareholders in the autumn of 2021. It expects to grow its revenue an average of 25% in each of the next five years. However, the company has accumulated substantial debt because of its acquisitions. As of the end of September 2021, it had $719 million in long-term indebtedness, offset by only $188 million in cash and equivalents. With interest rates expected to climb this year, Magnite's borrowing costs could go up, not to mention the effect higher rates have on growth stocks.

Nevertheless, Magnite remains a fast-growing company. When including results from the recent takeover of SpotX and SpringServe a year ago, the newly combined Magnite business grew CTV revenue 51% year over year, and its DV+ segment (all other digital video formats like mobile and desktop) grew at a mid-teens percentage in Q3. The company's free cash flow was $34 million in the quarter as well, good for a free cash flow profit margin of 26%.

While a high level of debt is worth monitoring, there's still a lot to like with Magnite. Even management thinks the steep decline in share price is a buying opportunity, as it announced a $50 million share-repurchase plan in December. If the company continues to grow at a fast pace this year, a rally could be in order.

3. Appian: Low-code development and software-based robotics are key business solutions

Digital process automation (DPA) firm Appian has been on an especially wild ride during the pandemic. After two short squeezes (in which traders betting against a stock close out their positions and cause a fast rally in share price), one last winter and a second over the summer of 2021, Appian is back to where it was in the early autumn of 2020, leading to the big 60% stock price drop in the last year.

That's the stock's performance, but the business itself has continued to chug along at a healthy pace. According to a recent report from researcher Forrester, Appian is a leader in DPA, combining its low-code software development platform with workflow mining and automation capabilities. This helps enterprises streamline their operations to become more efficient. It's a crowded space that includes some industry heavyweights like Microsoft and ServiceNow, but Appian has carved out a respectable place at the table.

In Q3 2021, total revenue increased 20% year over year to $92.4 million, driven by a 32% increase in the company's important subscription revenue segment to $67.2 million. Adjusted EBITDA was negative $12 million as Appian continues to spend heavily to support expansion, but with $188 million in cash and short-term investments on balance, the company can easily afford this strategy.

At the start of 2022, Appian stock trades for just under 13 times full-year anticipated revenue, not far off from the value it traded for at the start of the pandemic. If Appian continues to grow in the new year at a double-digit-percentage pace, the stage looks set for another run higher for this top play in software-based robotics and business automation.