The country's 100 biggest public defined benefit pension plansexperienced a funding increase of $185 billion in the firstquarter, thanks mainly to robust investment gains of 7.3 percent inaggregate, Milliman, a consulting and actuarial firm, reported Monday.

This improvement was the largest quarterly funding increasesince Milliman rolled out its public pension funding index inSeptember 2016. It came on the heels of the biggest quarterlydecrease of $306 billion in the fourth quarter.

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Milliman estimated that first quarter investment returns of thepublic DB plans ranged from a low of 3.5 percent to a highof 11.6 percent. As a result, it reported, their fundingstatus climbed from 67.2 percent at the end of December to71 percent at the end of March.

In a statement, the index's author RebeccaSielman said that even with the market fluctuations of the pastsix months, it was important to remember that the pensions havetime horizons measured in decades.

“Plan sponsors should take this volatility as a reminder toreview their asset smoothing policies, to ensure the short-termmarket fluctuations don't translate into short-term contributionvolatility,” Sielman said.

At the end of March, the PPFI deficit stood at $1.508 trillion,compared with $1.693 trillion at the end of December. Millimanreported that total pension liability continued to grow, to anestimated $5.205 trillion at the end of the first quarter, up from$5.164 trillion at the end of previous quarter.

Fourteen PPFI plans had funded ratios above 90 percentin the first quarter, six more than in the previous three-monthperiod.

At the lower end, 28 plans had funded ratios below60 percent, with nine plans stuck below40 percent funded.

Fifty-eight plans, one less than in the fourth quarter, werefunded between 60 percent and 90 percent.

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