The stock market has had a "good run" this year, but its rate of increase may slow down, the billionaire co-founder of Blackstone Group told CNBC on Thursday.
Schwarzman said the market "overshot on the way down, significantly" in the fourth quarter of last year, which saw the S&P 500 sink 2.7% on Dec. 24 to the lowest close of 2018. At the time, markets were responding to turmoil in Washington, including reports President Donald Trump was discussing how to remove Jerome Powell from his position as chairman of the Federal Reserve.
Markets were also concerned the world could enter into a global recession.
Since Dec. 24, however, the S&P 500 has rallied nearly 23% as of Wednesday's close, with the bulk of that advance coming in 2019. The Dow Jones Industrial Average is up 21%, while the Nasdaq is up 29%.
The chairman and CEO of private equity giant Blackstone, with $512 billion in assets under management, said he never thought that the U.S. was going into a recession.
The recession "didn't happen" and "China didn't fall off a cliff the way people were also saying," Schwarzman said. "Now [the market has] popped up and it is at a pretty good level."
Schwarzman joined CNBC as the investment firm announced it will become a corporation in July, shifting from its current status as a publicly traded partnership. The CEO said making the change will allow "double the number of people" who are able to buy Blackstone's stock.
Schwarzman outlined what he called a "Marshall Plan" for the middle class to address increasing income inequality in America.
Watch: Blackstone CEO Steve Schwarzman discusses the firm's shift to a corporation