POSTED: Friday, December 28, 2012 --- 9:10 a.m.

MADISON, Wis. (AP) -- Retired public employees in Wisconsin could see their monthly payments decrease as much as 13 percent next year.

The Department of Employee Trust Funds says in preliminary estimates that monthly payments to investors in the Wisconsin Retirement System's Core Fund are projected to either remain the same or drop up to 13 percent.

All of the roughly 167,000 people in the system get at least half of their pension in a Core Fund annuity.

Payments from the fund have dropped four years in a row, including 7 percent this year.

The fund's investments are still recovering from a more than 26 percent drop in 2008. Returns are smoothed out over a five-year period.

The exact amount that annuities will be adjusted will be released in March.

Copyright 2012: Associated Press