Following a long cycle of record-low interest rates, Fed Governor Jerome Powell is calling for central bankers to actively monitor financial excess, particularly where commercial real estate is concerned.

Though inflation is being managed, “overheating has shown up in the form of financial excess,” Powell said in a speech to the American Finance Association in Chicago this past weekend. He said the Fed must be diligent in its attempt to safeguard the financial system from a buildup of risks that could hit as a result of the low interest rate environment the country has experienced since the recession, Bloomberg reports.

CRE valuations in some markets are high, Powell said, and gross leverage in the non-financial corporate sector is high compared to historic standards. Fed officials are carefully monitoring President-elect Donald Trump’s plans for fiscal stimulus and contemplating how quickly they should raise rates as the country recovers from one of its longest periods of anemic economic growth. [Bloomberg]