Private pension fund levels fall behind

For many investors, last year's stock market gains helped make up for the heavy losses inflicted by the 2008 financial collapse. But it turned out to be a lousy year for private pension funds, which lost ground on their funding levels.

After gradual progress rebuilding the funds they need to pay retirees, the average private pension fund held about 80 percent of what it needs to cover those payments, according to a report by benefits consultant Towers Watson. That's down from 89 percent at the end of 2013 and represents an overall deficit among large corporate plans of about $343 billion, nearly double the shortfall a year earlier.

Much of the shortfall came from an increase in liabilities (or the amount they now expect to owe beneficiaries). Even as companies have pared back their defined-benefit plans—the ones that pay a guaranteed check for life—the cost of keeping that promise has increased. There are two big reasons: lower interest rates and longer life expectancies.

Low interest rates reduce the amount of money a pension fund can earn from money already set aside, raising the level it needs to generate enough cash. Interest rates also affect the way pension accountants estimate the future cost of writing all those retirement checks. Accountants look at something called the "time value of money" to compare how a given amount of money today will be worth decades in the future.

The other hit to pension funding levels came from the latest data showing that retirees are living longer than the long-term assumptions that were used to calculate how much their defined benefits will cost. Last fall, new mortality tables from the Society of Actuaries showed that between 2000 and 2014, longevity for the average male age 65 rose by two years to 86.6. For women age 65, overall longevity during the same period rose 2.4 years to age 88.8.

The SOA estimated that those gains in lifespan could add as much as 4 percent to 8 percent to a private pension plan's liability.

Pension funds did get some breaks from Congress, however.

One deal struck in Congress last summer to win support for an extension of the nearly insolvent Highway Trust Fund changes the way companies are allowed to account for the future cost of paying pension benefits to retirees.

In exchange for setting aside more money to fix an epidemic of potholes, Congress attached a rider allowing pension funds to "smooth" the way they account for long-term ups and downs of interest rates. That allowed companies to defer tens of billions in pension fund contributions, which the government expects to flow to the bottom line as bigger profits and generate higher corporate taxes.

The change makes a big difference in how much money companies now have to set aside, resulting in what amounts to a $51 billion corporate piggy bank. That's how much Moody's Investors Service estimated companies will save in lower pension fund contributions thanks to the road repair bill.

However, companies will still have to make up those payments in the future.

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In a separate move last month, lawmakers finalized a last-minute, behind-the-scenes deal to shore up the government's pension insurance fund by raising premiums and allowing some troubled pension plans covering more than one employer to cut retiree benefits.

The provisions, which drew loud opposition from unions and other groups representing retirees, were part of a massive $1.1 trillion spending bill signed by President Barack Obama last month.

Proponents argued that the changes would keep the failing pension plans afloat and keep benefits flowing to retirees. But some union officials and retiree advocates, such as AARP, slammed the benefit cuts as a sneak attack on a decades-old promise to workers and their families.

Read MoreCongress eyes move to cut pension benefits

The fix proposed by Congress would allow some underfunded multiemployer plans to cut the benefits they pay to some current and future retirees to help cover higher premiums to shore up the Pension Benefit Guaranty Corp., the government insurance fund backing these plans. (Benefits reportedly would not be cut for disabled pensioners or those 80 years and older.)

About a quarter of the roughly 40 million workers who participate in a traditional defined-benefit plan are covered by multiemployer plans, according to the Bureau of Labor Statistics.

Multiemployer plans are jointly backed by employers in industries such as construction, trucking, mining and food retailing. Although many of the approximately 1,400 such plans are in good shape, an estimated 1.5 million workers are in plans that are failing.

Both public and private pension funds were hit hard by the 2008 financial crisis, which wiped out trillions of investments used to pay retiree benefits. Since then, many private plans have recovered those losses and are on a more solid footing.

But multiemployer plans, which typically cover smaller companies and unions, face a different set of financial challenges. Declining union enrollments, for example, mean there are fewer active workers to cover the cost benefits for retirees, many of whom are living longer than expected when these plans were established.

Multiemployer plans also face the added burden of their pooled pension liabilities. When one member of the plan fails to keep up with contributions, the burden on the other members increases.

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