That is how long it has been since Donald Trump tested positive for the coronavirus and started to suffer from symptoms, according to the timeline the White House and his doctors have provided.
Typically, the most dangerous period for a coronavirus patient is 7-10 days after the onset of symptoms. That is when more severe cases can suddenly take a turn for the worse.
I'm not pulling that figure out of my backside. The 7-10 day window has been consistently mentioned by medical experts, including the President's own physician, Dr Sean Conley.
"In particular, days 7-10 are the most critical in determining the likely course of this illness," Conley said the first time he briefed the media on Trump's condition, on Saturday.
"He's doing so well, but with a known course of the illness, days 7-10 we get really concerned about the inflammatory phase."
Today, even as he endorsed Trump's decision to leave Walter Reed Medical Centre and return to the White House, Conley still acknowledged that danger period.
"You said that 7-10 days was a window that you'd be concerned about. I don't think we're there yet," a reporter reminded him.
"Do you have concerns about potential worsening or reversal? What are your plans for addressing that, if it were to happen?"
"You're absolutely right," said Conley.
"That's why we all remain cautiously optimistic and on guard, because we're in a bit of uncharted territory when it comes to a patient that received the therapies the President has so early in the course.
"We're looking to this weekend. If we can get through to Monday with him remaining the same or improving, then we will take that final, deep sigh of relief.
"He may not be entirely out of the woods yet."
Maybe the President will be fine. Maybe last Friday morning, when his blood oxygen levels dropped and he was moved to hospital, will end up being the most perilous moment he faces from the infection.
The point here is that we simply don't know yet. And in the estimation of Trump's own doctor, we will not know until Monday.
Why, then, is Donald Trump acting as though he has already beaten the virus?
In his upbeat video message to Americans today, filmed on the White House's Truman Balcony, Trump said he was "better" now, mused that he might be "immune", and told his constituents not to let fear of the virus "dominate" their lives.
"Don't let it dominate you. Don't be afraid of it. You're going to beat it. We have the best medical equipment, we have the best medicines, all developed recently. And you're going to beat it," the President said.
"I went, I didn't feel so good. And two days ago – I could have left two days ago. Two days ago I felt great, like, better than I've felt in a long time. As I said just recently, better than 20 years ago.
"Don't let it dominate. Don't let it take over your lives. Don't let that happen. We have the greatest country in the world. We're going back, we're going back to work. We're going to be out front.
"As your leader, I had to do that. I knew there's danger to it, but I had to do it. I stood out front, I led. Nobody that's a leader would not do what I did. And I know there's a risk, there's a danger, but that's okay.
"But now I'm better, and maybe I'm immune. But don't let it dominate your lives. Get out there, be careful. We have the best medicines in the world.
"The vaccines are coming momentarily. Thank you very much."
The US President also posted a bombastic, campaign-style video featuring triumphant images of his brief trip from Walter Reed to the White House. And he promised to be back on the campaign trail "soon".
The optimistic tone was echoed by Trump's supporters.
I was particularly struck by Republican Senator Kelly Loeffler, for example, who posted a photoshopped version of Trump's famous WrestleMania appearance, showing him quite literally beating the virus.
"Covid stood NO chance against Donald Trump!" Loeffler said.
Stood? Past tense?
We are four days into an infection that has been known to recede in some patients, only to quickly turn severe a few days later. Trump is still sick, and his fight against the virus is ongoing.
"It's now well established that a patient's wellbeing can suddenly change around 7-10 days after symptoms first develop, even when they feel on the mend in the meantime," Professor Daniel Davis, an immunology expert from the University of Manchester, told Newsweek today.
University of East Anglia Professor Paul Hunter told the magazine "you cannot give the all-clear for at least a couple of weeks".
"The times we are most concerned about with a Covid patient are days 7-10. Why is he being discharged now when the most concerning time is yet to come?" Dr Leana Wen, a visiting professor at George Washington University, wondered on PBS.
"What happens is, a person can actually get much more stable for a stretch, and then they have this disregulation of their immune system. Your immune system goes into overdrive," Dr Eric Topol, a cardiologist, told CNN.
"(It's) especially more common in people of an advanced age. So he's not out of the woods by any means."
There is no shortage of quotes like this from experts who worry the President might be claiming victory over the virus prematurely.
Nor is there any shortage of patients in this pandemic who wrongly thought they were past the worst of the infection.
In the United States, the most prominent example is the businessman and one-time Republican presidential candidate Herman Cain, who tragically died in July.
Cain tested positive for the virus on July 2. Throughout the month, the team running his social media accounts provided increasingly positive updates on his condition.
"The progress is slow but his breathing is getting stronger every day. Make no mistake, he is improving!" they said on July 10.
On July 15, they said doctors "like the progress he is making".
"He really is getting better, which means it is working," they said on July 27.
On July 30, he was dead.
Across the Atlantic Ocean, British Prime Minister Boris Johnson appeared to be suffering from a relatively mild case of the virus for about a week. Then, nine days after testing positive, he suddenly went to hospital.
Johnson's condition deteriorated rapidly and, according to the man himself, the situation became so grim that his doctors started to consider how they would announce his death.
"It was hard to believe that in just a few days, my health had deteriorated to this extent," he told The Sun in May.
"The bad moment came when it was 50/50 whether they were going to have to put a tube down my windpipe.
"They were starting to think about how to handle it, presentationally."
Obviously, Trump has access to unrivalled healthcare, and after his worrying episode on Friday, his doctors threw the proverbial kitchen sink at him.
He has received supplementary oxygen, zinc, vitamin D, the heartburn drug famotidine, the sleep aid melatonin, aspirin, the antiviral drug remdesivir, a steroid called dexamethasone, and an experimental cocktail of antibodies which is still in the clinical trial phase.
There are still some things his doctors will not reveal, such as whether or not there is any evidence of pneumonia or inflammation in the President's lungs, or when the date of his most recent negative coronavirus test was.
The latter could help us come up with a more accurate estimate of when, exactly, Trump was infected, and therefore where really he is in relation to the 7-10 day danger period. But Conley is not budging. He refuses to share the information.
When he spoke to reporters today, the White House physician sought to reassure Americans that Trump would continue to be well cared for back at the White House.
"He's returning to a facility, the White House medical unit, that is staffed 24/7. Top-notch physicians, nurses, logisticians," he said.
"Right now there's nothing that is being done upstairs here that we can't safely conduct at home."
So, even if Trump is growing complacent, his doctors are not.