If President Donald Trump wants to punish Amazon for lousy Washington Post coverage, it's working.
Amazon sank 5% Monday after Trump renewed his attacks on the company on Twitter. Its market value has fallen $37.4 billion since Trump first began targeting Amazon last week.
Trump once again accused Amazon of taking advantage of the US Postal Service, and he suggested that Amazon does not pay its fair share of tax. In fact, Amazon pays the same lower rate that the post office charges other bulk shippers, and it collects sales tax in every state that charges it.
The president has said he dislikes Amazon because CEO Jeff Bezos also owns the Washington Post. He has said without proof that he believes Bezos uses the newspaper to lobby for Amazon's business interests. Amazon does not hold a stake in the Washington Post.
Trump has tweeted about Amazon four times in the last week.
Amazon's drop is contributing to the broader market's fall. The Nasdaq tumbled 2.7% Monday.
"There's a regulatory cloud over all the tech names right now," said Jefferies analyst Brent Thill.
Apple, Amazon, Google, Microsoft, and Facebook made up nearly a quarter of the market value of the entire S&P 500 as of the end of February. They contributed to the market's climb last year. Amazon gained 56% in 2017.
Now some investors worry that tech companies have become too powerful to grow.
"When you're a $700 billion market cap, you become a target," Thill said. Amazon has a $663 billion market value after its fall. Trump's tweets could "keep a lid on the stock short term, but long term there's no real change to our positive thesis," he said.
Anthony DiClemente, an analyst at Evercore ISI, agreed that the fundamentals behind Amazon haven't changed and there were no signs that Trump's tweets had discouraged customers from shopping on Amazon.
Bill Smead, who runs Smead Capital Management, said he believes the company's price tag is unsustainable (he doesn't own the stock).
Amazon's price to earnings ratio, a measure of how expensive the stock is compared to every $1 of earnings, sat at 223. The average ratio on the S&P was 27.5.
"It is absolutely inevitable that at some point the very, very high multiple that gets attached to them becomes a curse."
-CNNMoney's Paul R. La Monica contributed to this report.