Principal Financial Group Inc., the nation’s largest manager of 401(k) retirement plans, said it has restructured into three units in a move that will make each division responsible for the distribution of its products.

Previously, the marketing and sales of Principal’s products, which include different types of 401(k) plans, annuities and disability and medical insurance plans, was handled by a separate division overseen by Executive Vice President Michael Daley. As a result of the changes, Daley, 47, will leave the company, according to Principal spokeswoman Tina Marchetti.

The new structure will make the heads of the three business units directly responsible for profits and losses and will help streamline Principal’s operations, the company said.

“Each division president will have complete control over profits and losses and will be able to drive performance to an even higher level,” Marchetti said. “It will help intensify performance.”

Under the changes, John Aschenbrenner has been named president of insurance and financial services, which includes Principal’s life and heath insurance businesses and its mortgage banking operations. Larry Zimpleman was named president of retirement and investor services, which includes U.S. and international asset accumulation and the quickly growing Principal Bank.

James McCaughan remains president of Principal Global Investors, which handles global asset management, and Michael Gersie will continue as chief financial officer.

Prior to the changes, the company had five executive vice presidents. Now, it has two, Gersie and McCaughan.  The former distribution division employed 1,600 people in Des Moines, plus another 1,000 agents across the nation. Those workers will be folded into the business units that they represent.