JEFFERSON CITY, Mo. -- Performance bonuses will continue for workers at the Missouri State Employees' Retirement System, but its salary structure will be studied.

Staff at the retirement system were paid about $460,000 last year. That drew criticism from Gov. Jay Nixon and some lawmakers, because the fund lost nearly one-third of its value in 2008.

The retirement fund's board on Thursday approved a salary study to be completed by Dec. 31. But Kelvin Simmons, Nixon's commissioner for administration, was defeated when he tried to strip money for the extra pay from the system's budget.

MOSERS executive director Gary Findlay said Missouri's retirement system is outperforming its peers and attributed that to the incentive pay.