Federal Reserve Bank of Atlanta President Dennis Lockhart said the absence of inflationary forces in the economy five years into the recovery is “puzzling.”

Growth picked up in the second half of 2013, and “at the same time we just don’t see any inflation to speak of,” Lockhart said in reply to a question after a speech at Mercer University in Macon, Georgia. “Generally you would expect inflation to be associated with growth.”

“Does that suggest we are misreading the underlying strength of the economy? It’s possible,” he said. Still “my outlook is we will gradually see a rise in inflation” as growth picks up.

Lockhart also said Fed policy makers may need to consider different measures of labor-market strength in addition to the unemployment rate.

It may be necessary to “at least give equal time to some other approach,” for example, “a range of unemployment statistics that as a group can give a pretty accurate picture of the health of the labor market.”