NASRA’s latest update to standing issue briefs, Public Pension Plan Investment Return Assumptions underscores the critical role the investment return assumption plays in the financial health of public pension plans. Of all actuarial assumptions, it has the greatest impact on plan funding levels and cost. This brief traces how a decade of low interest rates and inflation, beginning in 2009, prompted many plans to reduce their long-term expected returns in line with more modest capital market projections. However, since inflation began rising in early 2021, the trend toward lowering return assumptions has largely paused. While reducing a plan’s assumed return can increase both costs and unfunded liabilities, setting this assumption is a careful, thorough process. It draws on expert input from actuaries and investment professionals and is guided by actuarial standards of practice.
