Many private sector pension plans have taken a beating in these difficult economic times. Some companies have slashed current and future benefits, frozen employer contributions or dropped plans altogether, continuing a trend that started even before the economic downturn.

With private sector workers shouldering a greater responsibility for retirement savings, it's not asking too much for Minnesota teachers and school districts to pay a little more to keep their pension fund financially healthy.

A legislative proposal to increase the contributions of school districts and teachers to the statewide retirement fund merits passage. The plan is an equitable way to shore up the pension pot and keep it viable in the future. Modifying the contributions now will ensure that retirement benefits will be available for the 77,000 educators who currently pay into the plan and were promised a modest retirement income as a condition of employment.

Without increased contributions, the fund is in trouble. As of last June, the Minnesota Teacher Retirement Association (TRA) had assets of about $17.8 billion, while liabilities to current and future retirees totaled $23 billion, leaving a $5.2 billion gap.

Fund managers project that without an infusion of new money, the fund will go broke by 2032. That would leave thousands of future retirees without the income they had paid to support during their careers.

The major feature in the legislation would increase both district and teacher contribution rates, which are currently 5.5 percent. Those rates would each rise by 0.5 of a percentage point annually over a four-year period up to 7.5 percent. For the average working educator making about $49,000 per year, that additional payment would be $172 in the first year and $686 in 2014. During the first year, the higher contributions would raise $40 million to $42 million for the TRA fund -- half paid by teachers and the other half by school districts.

In addition, the bill would temporarily freeze benefit increases for the 50,000 educators who now receive pension checks. Under current law, retired teachers receive a 2.5 percent annual bump as a cost-of-living increase. Retirees would not get that increase in 2011 and 2012, costing them about $700 per year. In 2013, the raise would be lowered to 2 percent; when the fund is restored to at least a 90 percent level, the 2.5 percent would be reinstated.

Education Minnesota officials have raised concerns about the bill but say their position is more nuanced than flat-out opposition. Tom Dooher, president of the teachers union, said the organization is not necessarily opposed to raising pension contribution rates of teachers, but it wants assurances that educators won't have to cover the entire pension shortfall if school districts fail to provide additional funding.

Raising contributions and withholding increases spreads the financial pain among the active teachers, school districts and retirees. And in future years, when the market and pension coffers are healthier, adjustments could be made to decrease the contributions.

During the go-go years in the stock market, the teacher pension fund was fully funded between 1997 and 2004. Times were so good that fund operators were able to decrease employee and employer contribution levels. But those rollbacks, combined with sharp market downturns after 9/11, in 2002, 2008 and 2009, depleted the fund.

The shared sacrifice approach outlined in the proposed legislation is a fair way to keep an important public pension plan solvent. Legislators should pass it to protect the current and future retirement incomes for tens of thousands of Minnesotans.