SIOUX FALLS, S.D. (AP) — The South Dakota Retirement System is planning a big change to the 40-year-old pension plan that covers more than 77,000 employees of state and local governments.

Instead of increasing retirees' usual benefits the next time the system has a surplus, Retirement System leaders want to add a new benefit.

Retirement System director Rob Wylie tells The Argus Leader the system wants to add a defined contribution plan like a 401(k). He says the defined contribution plan would be on top of the existing defined benefit provision, which will not go away.

Wylie says many details of the idea have not been finalized.

Copyright 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.