Billionaire investor Bill Ackman says Fed rate hikes are likely over but warns a 'big threat' still looms

• Bill Ackman said the Fed is likely done hiking interest rates as the economy starts to weaken.
• "High mortgage rates, high car rates, high credit card rates — they're starting to have an impact on the economy," he told CNBC.
• The billionaire investor is also betting that 30-year Treasury yields are going to rise further.

Bill Ackman, CEO of Pershing Square Capital Management, said that the Federal Reserve is likely done hiking interest rates as the economy begins to signal a slowdown, but warned spillover effects will continue.