J. Barry Griswell will continue to be the chairman of Principal Financial Group Inc. until the end of the year, the company says.

Principal, Des Moines, Iowa, had announced in February that Griswell would turn both the positions of chairman and chief executive officer over to Larry Zimpleman, the company’s current president, May 1.

Now Griswell intends to serve as chairman for a few months longer, Principal has announced in a document filed with the U.S. Securities and Exchange Commission.