President Donald Trump tweeted early on Friday that he was "looking forward" to the May jobs report, which he had access to the night before.
This unusual move may have signaled to some traders that the report was good.
Gold extended its declines, while bond yields moved higher after Trump's tweet.
At 7:21 a.m. ET on Friday, Trump said he was "looking forward to seeing the employment numbers at 8:30 this morning." The president and other senior members of his administration are privy to the numbers a day before their release, but a Bureau of Economic Analysis rule bars executive-branch employees from commenting until an hour after the numbers are officially made public.
Apart from the government employees who work on the report, the other people with early access are a small group of reporters, locked up in a room without cellphone or internet access until after 8:30 a.m.
That is because the jobs report is viewed as one of the most important indicators of the US economy and often moves markets.
Josh Wright, a former Federal Reserve staffer who is now the chief economist at the recruiting-software firm iCims, called the tweet "a significant violation of prior norms, at the least."
Trump's tweet may have signaled to investors that the numbers were good, and they turned out to be: nonfarm payrolls increased by 223,000, more than economists expected, while the unemployment rate fell to an 18-year low of 3.8%.
Gold slid sharply just minutes before the report but had been dropping before Trump's tweet:
Bonds also sold off through the morning, and yields rose:
Investing.com; Business Insider
"We have rules in markets for a reason: so that we have a fair and level playing field," Wright told Business Insider.
"Anything that changes the appearance of whether it's a fair and level playing field really is a threat to our economy."
The White House press secretary, Sarah Huckabee Sanders, told CNBC the tweet was acceptable because the president "didn't put the numbers out."
Though Trump's tweet suggested a strong jobs report, it may not have been the White House's first time giving clues on the numbers.
"People need to stop being so woke," said Neil Dutta, the head of US economics at Renaissance Macro. "Before Twitter, the fixed-income desks across Wall Street often used snap press conferences in the Rose Garden on NFP Fridays as a sign of whether or not the jobs number would beat estimates."
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