After rising to its highest level in four months in January, NISA Investment Advisors' Pension Surplus Risk index fell 50 basis points in February to 9.8%.
According to NISA, the drop was driven by decreases in both the volatility of return-seeking assets and interest rates.
The PSRX aims to be a forward-looking estimate of the funded status volatility of U.S. defined benefit pension funds, based on averages of the 100 largest corporate plans.
The average funded status of plans in NISA's universe rose to 89.3% in February, up from 87.9% the previous month.
