June 20 (UPI) -- Shares of Slack climbed rapidly as the company made its initial public opening Thursday on a record day for the S&P 500.
The company, which provides messaging software for companies, opened at $38.50 on the New York Stock Exchange and rose to $38.62 by the time the markets closed, exceeding its reference price of $26.
Slack's valuation rose to $19.5 billion at the end of trading, up from $7.1 billion as a private company.
Slack went public through an uncommon practice known as a direct listing in which the company began trading its stock without issuing new shares or raising capital, as it has $793 million in cash in reserve.
"Starting three years ago, we started trying to run Slack as a public company," Slack CEO Stewart Butterfield said. "We have been building toward this for a long time."
Slack's IPO came on a strong day for the stock market as the S&P 500 soared to a record close, rising nearly 1 percent to 2,954.18 amid speculation that the Federal Reserve will lower interest rates next month.
The Dow Jones also rose about 1 percent or 249 points and the Nasdaq Composite rose 0.80 percent.
The yield on the 10-year Treasury fell below 2 percent for the first time since November 2016 and the Fed said it was prepared to combat economic risks amid trade tensions and concerns about inflation.
President Donald Trump said Thursday that he believes Fed Chariman Jerome Powell should have taken action on lowering the interest rate earlier this year.
"He should've done it sooner, but what are you going to do? Can't win them all," Trump said. "Eventually he'll do what's right, perhaps. Let's see what he does."