The S&P 500 (^GSPC 1.02%) slipped into a bear market at the beginning of 2022. While the benchmark index is still down 9% from its high, it has climbed 20% from the low point in reached last October. That milestone is portentous for two reasons. First, many investors see it as a signal of a new bull market. Second, it hints at continued momentum in the coming months.

Since the mid-1950s, the S&P 500 has bounced 20% from its bear-market lows on 13 different occasions, and the index returned an average of 17.7% during the one-year period that immediately followed those events. That means history has a clear message for investors: The S&P 500 could soar in the very near future.

Here are two exceptional growth stocks to buy now and hold forever.

1. Paycom Software

Paycom (PAYC 1.24%) offers a broad suite of human capital management (HCM) solutions. Its core product is payroll software, but the company also provides applications for recruitment, training, scheduling, and benefits administration. Its all-in-one platform is a key differentiator because most businesses currently rely on multiple vendors to meet their HCM needs, a strategy that burdens administrative staff with complicated integrations and time-consuming maintenance. But Paycom simplifies HCM by allowing clients to manage the entire employee life cycle from a single dashboard.

Paycom has also differentiated itself through product innovation. In 2021, it introduced the first self-service payroll software in the HCM industry. The product, nicknamed Beti (Better Employee Transaction Interface), automates payroll by requiring employees to review and approve their paychecks prior to processing. That ultimately helps clients operate more efficiently by reducing time spent fixing payroll errors.

The labor market has been resilient despite difficult economic conditions, and Paycom capitalized on that with solid financial results in the first quarter. Revenue rose 28% to $452 million and GAAP earnings climbed 30% to $2.06 per diluted share. Of course, that momentum could stall if the economy slips into a recession. Unemployment tends to rise during economic downturns and Paycom generates some revenue on a per-user basis. But the company remains well positioned for growth in the long run.

Paycom holds just a 5% HCM market share in the U.S., according to CEO Chad Richison, but its broad portfolio and innovative payroll software should bring more domestic clients to its platform in the future. Additionally, the company recently expanded into international markets with the launch of Global HCM, a product that will make its HCM software available in over 180 countries. That represents a hitherto untapped opportunity.

Currently, Paycom shares trade for 12.3 times sales, a bargain compared to the three-year average of 20.6 times sales. That creates a compelling opportunity for patient investors to buy this growth stock.

2. Zscaler

Zscaler (ZS 1.28%) is a cybersecurity company that specializes in cloud workload protection and zero-trust network access. Its security service edge (SSE) platform modernizes corporate networks by inspecting traffic and enforcing zero-trust policies in the cloud rather than private data centers. That means clients can protect their applications and workers without the cost and complexity of on-premises security appliances.

Zscaler has distinguished itself through scale. It operates the largest network security cloud in the world, handling 300 billion requests and collecting 500 trillion security signals each day. That data advantage makes its artificial intelligence (AI) engine particularly good at detecting attacks, which ultimately allows Zscaler to provide better protection than other vendors. CEO Jay Chaudhry recently said its platform "offers better security and user experience while substantially reducing cost and IT complexity compared to legacy networking and security."

Zscaler reported impressive financial results for the third fiscal quarter (ended April 30, 2023), beating expectations on the top and bottom lines. Revenue rose 46% to $419 million and non-GAAP net income soared 182% to $0.48 per diluted share. More significantly, the growing importance of cybersecurity means Zscaler is set to maintain that momentum.

Consultancy Gartner recently acknowledged Zscaler as a leader among SSE providers for the second straight year, but the company has hardly dented its $72 billion addressable market. That combination leaves plenty of upside for shareholders. But Zscaler is also adding new products and features to its platform to keep itself on the cutting edge of the industry and expand its total addressable market. The company's latest innovation is a suite of security capabilities engineered specifically for generative AI applications.

Currently, Zscaler shares trade for 14.1 times sales, an absolute bargain compared to the three-year average of 35.4 times sales. Investors should take advantage of the discounted price by purchasing a few shares of this growth stock.