The funded status of defined benefit pension plans of S&P 1500 companies remained at 84% in September, said a monthly report from Mercer.
Falling equity markets offset a drop in liabilities, holding the funded status stable.
U.S. equity markets fell 1.6% in September, countering a $180 billion drop in liabilities, the largest monthly decrease in liabilities this year. The decrease was driven by rising discount rates, which increased 20 basis points to 4.1% in September.
The collective estimated deficit of $352 billion at the end of September is down $17 billion from the end of August and up $116 billion from the end of December, Mercer said.
Estimated aggregate assets totaled $1.85 trillion as of Sept. 30, up 2.8% from Dec. 31. Estimated projected benefit obligations were $2.21 trillion, up 8.9% from the end of December.
“Rising interest rates gave us our largest monthly decrease in pension liabilities this year, but unfortunately the reduction in liabilities was largely offset by losses on assets,” said Jim Ritchie, a principal in Mercer's retirement practice, in a news release. “This change in trends in 2014 is a good reminder that plan sponsors should stress test their risk management strategies to better understand how their strategies will hold up when markets change course.”