As workers worry increasingly about having enough money to seethem through retirement in reasonable comfort without running out,as well as wanting to be able to move their retirement plans fromjob to job, a report from the National Institute on Retirement Security toutspublic defined benefit pension plans as meeting both thoseneeds.

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The study was based on a survey of 89 public pension plans todetermine plan types, employee contribution rates, vestingrequirements, interest rates paid on withdrawn employeecontributions, refunds of member accounts, redeposits of employeecontributions and ability to purchase service credits.

As the private sector has increasingly moved away from definedbenefit plans to defined contribution plans, the study said thatmigration “has resulted in a ‘great risk shift’ where the risk andmost of the funding burden falls in individual employees, ratherthan experienced professionals and employers.” Because of thatshift, it said, “the median retirement balance for all working-agehouseholds is only $2,500; for households near retirement, thebalance only marginally improves to $14,500.”

And although employees in the private sector are glad to be ableto move their accounts when they switch employers, the report said,far too many don’t — instead, they cash out their plans and end upshort when it comes time to retire.

Defined benefit plans, in contrast, aren’t necessarilyviewed as being portable — but the report said that wasn’tnecessarily the case. Many public pension plans, it said “haveadopted features that allow individuals who change jobs to retainand even increase their benefits.”

Another difference between defined contribution and definedbenefit plans is the voluntary nature of the former, withemployees usually having to opt in — although the use of autoenrollment is growing. But nearly all public pension plans, thereport said, “consistently require employees to contribute towardthe cost of their retirement benefits as soon as they startworking, and to continue with every paycheck.”

Then there’s the annuitized nature of defined benefit planbenefits — something that the defined contribution market isworking to catch up on. In addition, there’s the question ofwhether private sector employees have access to a retirement planat all — the paper said that just 55 percent of private sector wageand salary workers between the ages of 25 and 64 had access to aretirement plan at work in 2013.

The study did not address the funded levels of any publicpensions — something that’s made headlines for the precariousnature of many plans’ finances. Membership in Washington,D.C.-based National Institute on Retirement Security is comprisedof financial services firms, employee benefit plans, tradeassociations and other retirement service providers.