Estimates of how hard coronavirus will hit the economy are rolling in. And they are terrifying

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Things are bad. But according to upcoming economic data estimates, they could get a lot worse.

While markets have sold off at record levels (the S&P 500 was down around 30% from its high as of Monday), the rapid decline into a bear market hasn’t left much time for economic data to play into it. To those like Matt Miskin, co-chief investment strategist at John Hancock Investment Management, “It’s going to get dire before we start getting better.”

In fact, following widespread closures of bars, restaurants, and the dislocation of other business activities and supply chains, stats like jobs data for March are still forthcoming—and the estimates are sobering.

Former Trump administration economist Kevin Hassett warned Monday that the U.S. could see up to 1 million jobs lost in March—telling CNN that “You’re looking at one of the biggest negative job numbers we’ve ever seen.” However, others like Russell Price, chief economist at Ameriprise, disagree, telling CNN companies will likely be “cautious about cutting workers if they think this will be a short-term phenomenon.”

Yet for those like Morgan Stanley Wealth Management’s chief investment officer Lisa Shalett, the main data piece markets don’t know how to “calibrate” is the impact to unemployment data. The number of workers who have already been furloughed or impacted by the outbreak could likely produce “eye-popping” unemployment data—in the hundreds of thousands or even 1 million jobs lost for March, Shalett notes. “That is going to be a critical piece of this,” she tells Fortune.

Still, the fallout of coronavirus’ impact on the economy is just starting to show in data. On Monday, a regional manufacturing index, the Empire State manufacturing index, read at its lowest level since 2009—down to negative 21.5 in March (down 34.4 points from the previous month). According to Miskin, that index is “the tip of the iceberg of this deluge of data that’s likely to come in more negative,” he tells Fortune.

That negative data will start showing up in the manufacturing and non-manufacturing ISM data, says Mike Ryan, UBS chief investment strategist for Wealth Management Americas, who anticipates readings to plunge into the mid-40s (February readings were 50.1 for manufacturing and 57.3 for non-manufacturing. Readings under 50 suggest contractionary conditions). The Markit (flash) manufacturing and services PMIs are due next Tuesday—two key previews of how badly economic activity may be hurt. Ryan surmises: “Is the worst economic data yet to come? Absolutely. Could we see further downside? Yes, of course.”

Weekly jobless claims, which will be reported on Thursday, are estimated to come in at around 220,000, up from 211,000 (for the week ending March 7)—but still operate on a lag, when coronavirus hadn’t reached its current impact in the U.S.

GDP, meanwhile, will almost certainly be negative in the 2nd quarter, experts say, with some estimating -2% to -5% GDP. John Hancock’s Miskin says he’s even estimating GDP could be as low as -10% in the 2nd quarter, noting “Our base case is that we do see a recession this year.”

Consumer spending has been (and will be) a key metric to watch, but is likely to be a pain point in coming months, as attempts to buoy the economy through fiscal policy amid widespread quarantines due to coronavirus could be a “more challenging event for policy makers to address than any really in recent history,” notes Miskin, because “If you get an extra paycheck, it’s not like you’re going to go out and spend it immediately—you’re not leaving your house.”

But how will markets respond?

Goldman Sachs is predicting the S&P 500 might see a midyear trough at 2,000—41% down from its all-time high. And John Hancock’s Miskin says that 10% to 15% more downside isn’t something that should be surprising. However, UBS’ Ryan says markets are likely pricing in the bad news, and don’t necessarily need good news to find a support level—instead, understanding the policy response from the administration and the actual economic fallout should give investors a better idea of what the downside is, and therefore more certainty.

And for Morgan Stanley’s Shalett, markets have largely already priced in both a recession and weak ISM and PMI numbers (she says they’re likely expecting readings in the low 40s)—and the bottom could be somewhere around 10% below Thursday’s 2,300 mark for the S&P 500.

But until we’re able to see the data roll in, investors are still largely in the dark about how bad the fallout might be.

“It’s more imperative now than ever … to use [your] own eyes and look around, because it is difficult—every economic data point is now lagging pretty significantly, and you really just have to do the calculus. If you close restaurants, all these social events … that has a massive impact to economic activity, and it’s not just in the U.S.,” Miskin says.

As markets wait with baited breath for the latest slew of data (and a potential fiscal package), UBS’s Ryan puts it in perspective:

“I remember I was sitting at a trading desk during the ‘87 stock market crash, I was there in ‘89, I was in research in ‘98 and 2000 and 2001 and 2008 and 2009—I’ve seen multiple market events, … no two play out exactly the same way,” Ryan recounts to Fortune. What’s different about this one, says Ryan, is how fast markets have been drawn down. “This has now become the most significant event that we’re discussing not just locally, but globally.”