Zillow Group Inc. shares plunged today as investors digested the news that the company was pulling the plug on its tech-powered home-flipping operation.

The stock dropped as much as 15.7% to $72.06, the biggest intraday slide since March 2020.

The home-flipping halt raised major questions about what’s next for a company that was pushing deeper into the U.S. housing market as part of its bid to transform itself from an online listings giant into a buyer and seller of thousands of homes a month.

“It’s a drastic and unexpected move,” said Ygal Unitarian, an analyst at Wedbush. “It was a central part of what the company was built on over the past three years, and management needs to go back to the drawing board and fill in the gap as it continues to aim to be a bigger part of the overall real estate transaction.”

Zillow shares nearly tripled in 2020 as the company rode the pandemic housing rally, closing the year at $135.94. But the stock has been sliding this year, taking a major hit as problems emerged in the flipping unit.

Zillow said Tuesday that was it shutting down the operation. Analysts reacted by slashing the company’s price targets.

Zillow iBuying push, key to the company’s future growth, collapsed when its vaunted pricing algorithms proved unequal to the task.

The Seattle-based company plans to take writedowns of as much as $569 million and reduce its workforce by 25% as it winds down the business in the coming months, according to a statement Tuesday.

Zillow’s third-quarter results showed it lost more than $380 million in the operation, called Zillow Offers.

The business hit a major snag in recent months as Zillow tweaked its algorithms to make more aggressive offers, causing it to overpay for houses just as the heated U.S. market began to cool slightly.

With the company’s losses mounting, Chief Executive Officer Rich Barton said it had become too risky to scale the business in a U.S. housing market that has been running hot for well over a year during the pandemic.

“Fundamentally, we have been unable to predict future pricing of homes to a level of accuracy that makes this a safe business to be in,” Barton said on an earnings call.

The problems with Zillow Offers burst into public view Oct. 17, when Bloomberg News reported the company was halting new offers on homes for the rest of the year. Zillow blamed a labor shortage, saying there weren’t enough workers to repair the properties it had under contract.

But in recent weeks it became clear the company had overpaid for homes and was taking mounting losses on the sales.

On Monday there was another sign that something had gone wrong: Bloomberg reported that the company was marketing about 7,000 homes for roughly $2.8 billion to institutional investors.

For most of Zillow’s 15-year history, the company has been known for publishing online real estate listings and home-price estimates — called Zestimates — and seeking to profit by connecting agents with potential clients. In 2018, Barton, one of the company’s founders, reclaimed the role of CEO and pivoted into the high-tech home-flipping business, called iBuying.

Zillow used pricing algorithms to buy homes from their owners, make light repairs, and put them back on the market. Barton set an ambitious goal, seeking to buy 5,000 homes a month by 2024.

The company will continue selling homes for at least a few months. It bought nearly 9,700 homes in the third quarter and expects to purchase another roughly 9,000 in the final three months of the year.

The company said it will take a writedown of as much as $265 million on home purchases that will close in the fourth quarter. That comes after the company misjudged the housing market.

“Zillow missed the offramp,” said Mike DelPrete, a real estate tech strategist. “It’s like you’re driving on the highway and you see brake lights ahead of you. You take your foot off the gas, you pump the breaks. Zillow didn’t do either of those things until it was too late.”