Slack’s valuation is roughly based on the workplace chat and collaboration software company’s projected revenue and current growth rate, said the people, who asked not to be identified discussing private talks.

The expected value is up from the $7.1 billion in its last private funding round in August. It’s similar to the company’s share sales on the private market, where in April investors were snapping up stock at prices that would give the company a valuation of about $16 billion.

A spokeswoman for Slack declined to comment.

Slack is planning to have its shares start trading June 20 on the New York Stock Exchange under the ticker WORK.

Investors’ valuation expectations are based on some back-of-the-envelope math: Slack said Monday that it expects at least $590 million in revenue in its 2020 fiscal year, which ends January. That’s a growth rate of as much as 50% compared with the previous year.

That suggests the company could bring in almost $900 million in fiscal year 2021, and investors are looking to value the company at roughly 20 times that projected revenue, the people said.

That’s even as the annual revenue growth rate has slowed from 110% and 82% in the 2018 and 2019 fiscal years, respectively, according to a regulatory filing.

Slack said in its filings with the U.S. Securities and Exchange Commission that it can’t guarantee that its plans to increase revenue and cut operating losses will ever allow it to become profitable.

Slack is also rolling out partnerships with other software companies. Dropbox Inc., the document-management software developer that went public last year, announced on Tuesday that it had integrated Slack into its workplace product.

Unlike a surge of tech companies that have gone public this year in traditional initial public offerings, Slack is going public through an unusual direct listing. The company won’t issue new shares to raise funds for itself. Rather, its investors will be allowed to begin selling existing shares immediately.

New technology stock offerings have been on the upswing this year. On Tuesday, CrowdStrike Holdings Inc. raised $612 million in one of the largest cybersecurity company IPOs ever.

Goldman Sachs Group Inc., Morgan Stanley and Allen & Co. are advising Slack on the listing. Bloomberg Beta, the venture capital arm of Bloomberg LP, is an investor in Slack.