Last week the stock market enjoyed a strong rally, and one part of the good news was the Treasury’s announcement that they didn’t have to borrow as much money as they had expected, which, given our $1.7 trillion budget deficit this year (up $300 billion over last year), is hardly great news. But the markets bought it anyway.

Then yesterday the results of the latest Treasury bond auction came in, and the stock market tanked in the afternoon. Here’s how Barron’s described it:

30-Year Treasury Auction Breaks Bad, Sinks Stock Market

The Treasury’s auction of 30-year bonds on Thursday went about as badly as it could, indicating investors are reluctant to own long-dated government securities.

At the auction of government debt that matures in 30 years, investors were awarded 4.769% in yield, 0.051 percentage point higher than the yield in pre-auction trading. The difference between the two yields—called a tail—indicated a weak auction where the U.S. government had to entice investors with a premium over the market to buy their debt.

Primary dealers, who buy up supply not taken by investors, had to accept 24.7% of the debt on offer, more than double the 12% average for the past year.

“Today’s 30 yr auction was outright bad,” Peter Boockvar, chief investment officer at Bleakley Financial Group, said in a research note.

Maybe this has something to do with the hesitations of the bond market: