Assumptions and Methods for 2024 Valuation Projections Model
Summarizes the assumptions and methods for the Office of the State Actuary’s 2024 Valuation Projections Model.
1. Background and disclosures
Background
On an annual basis, we produce an Actuarial Valuation Report (AVR) for Washington State retirement systems. We also prepare a Projections Model for the linked AVR. Each serve their own purpose as described below.
The AVR relies on participant and financial data from a single point-in-time and set of best estimate assumptions. This is known as “closed group” analysis meaning the model assumes no new members join open plans after the measurement date. These valuations are the basis for monitoring funding progress and determining on-going contribution rates consistent with the state's funding policy. A single point-in-time measurement is helpful in tracking changes and trends across multiple AVRs. However, the AVR is limited by only providing results for a single measurement date. For estimates beyond the measurement date, we rely on our Projections Model.
Our Projections Model is like the AVR but includes additional assumptions and methodology for experience beyond the measurement date. For instance, we make assumptions for demographics of new entrants and how many new entrants annually join the retirement plans. This allows the Projections Model to estimate funding progress and contribution rates at future measurement dates. In other words, the model estimates future annual AVRs. We generally rely on two modes for the model: “deterministic” and “stochastic”. The deterministic setting assumes all future experience is consistent with our best estimate assumptions. This tells us the state of the retirement systems on an “expected” basis. The stochastic model helps us understand the impact to the retirement systems if future experience does not match our assumptions. Our stochastic modeling primarily focuses on 2,000 simulations of investment returns scenarios. We summarize the results of our stochastic modeling in our annual Risk Assessment.
Disclosures
The 2024 Valuation Projections Model reflects the contribution rates that were adopted by the Law Enforcement Officers’ and Fire Fighters’ Plan 2 Retirement Board (LEOFF 2 Board) for the 2025-27 and 2027-29 Biennia. For all other retirement plans, we modeled the 2025-27, and where applicable 2027-29, contribution rates prescribed under ESSB 5357 (Ch 381, L 2025).
In addition to revising contribution rates, ESSB 5357 made changes to funding policy by setting the assumed investment rate of return to 7.25% for all systems except LEOFF 2. Consistent with the bill, our Projections Model also consolidates current benefit improvement amortization contribution rates into a single rate that will be paid from July 1, 2029, through June 30, 2040. We assumed this single rate was 0.38% for PERS 1 and 0.75% for TRS 1 based on our fiscal note analysis of ESSB 5357.
Unless noted otherwise, we rely on data, assets, assumptions, and methods from the 2024 AVR for our Projections Model. However, additional assumptions and methodology are required for the Projections Model. These include new entrant [or members hired after the measurement date] and stochastic analysis assumptions. These assumptions and methods are generally updated annually and disclosed below. We disclose the remaining assumptions and methods in the Projection and Risk Assumptions Study (PRAS) webpage since they are not updated as frequently. Please see the link to the PRAS webpage for additional supporting information.
We prepared the Projections Model to support our work products as well as proactively address stakeholder questions related to expectations for the future. We believe the set of data, assets, assumptions, and methods used for the work products that rely on the Projections Model are reasonable, but use of another set may also be reasonable and might produce different results. We expect this model will be updated during fall of each year. Kyle Stineman (ASA, MAAA) meets the Qualification Standards of the American Academy of Actuaries; he served as the reviewing and responsible actuary for the 2024 Valuation Projections Model.
2. Demographic assumptions
Plan Growth
Our Projections Model assumes the Washington State retirement systems will be larger in the future. We use the System Growth assumption developed during the most recent PRAS to estimate the annual growth; however, the annual growth rate may differ after reflecting our Plan Choice assumption. Please see this table for a comparison of our system growth rate assumption by plan.
Please note that while an individual plan may show a negative growth rate, we still assume the plan has new entrants each year according to the Plan Choice assumptions. For instance, the number of current members assumed to exit Teachers’ Retirement System (TRS) Plan 3 is greater than the number of assumed new entrants into that plan, but overall, the entire TRS system is expected to grow.
Demographics of New Entrants
The assumed demographics of future new entrants in the Washington State retirement systems are summarized in the New Entrant Profiles tables.
3. Economic assumptions
Discount Rate
The discount rate (or valuation interest rate) is the rate we use to determine the present value of future salaries and present value of future benefits. Consistent with the AVR, the discount rate assumption for projections is 7.25 percent for all retirement plans except LEOFF 2 (7.00 percent for LEOFF 2).
Return on Assets
Our deterministic and stochastic projections rely on the total commingled trust fund (CTF) return for fiscal year 2025. As of publication of this webpage, we have not received the FY 2025 return. We expect to have the FY 2025 return added to our Projections Model by early October. For deterministic projections, we assume a 7.0 percent return on investments each fiscal year beyond 2025 for all retirement plants except LEOFF 2 (7.00 percent for LEOFF 2).
Stochastic projections rely on a distribution of possible investment returns to calculate potential future outcomes. Our stochastic projections use a unique non-normal distribution of investment returns provided by the Washington State Investment Board (WSIB). This distribution reflects WSIB’s 2025 Capital Market Assumptions with the commingled trust fund asset allocation adopted by WSIB in October 2021. The Investment Return distribution provides a summary of the range of investment returns we might expect in a single year. The range of returns we expect over a longer period will vary from the distribution of returns for a single year.
Inflation
For deterministic projections, we assume 2.75 percent inflation for all systems consistent with the AVR.
Stochastic projections rely on a distribution of possible inflation rates to calculate potential future outcomes. The Inflation distribution provides a summary of the range of inflation rates we might expect in a single year. The range of inflation we expect over a longer period will vary from the distribution of inflation for a single year. Stochastic inflation projections are used to project LEOFF Plan 1 benefit payments, which receive an uncapped Cost-of-Living Adjustment (COLA).
4. Miscellaneous assumptions
Assumed Funding Sources
Where an individual works determines how their contributions are allocated from the various sources used to fund retirement benefits. The Projected GF-S Fund Splits table summarizes our assumption for what percent of total employer contributions, for each system, will be allocated from General Fund-State, Non-General Fund-State, and Local Government accounts. The PERS, PSERS, and WSPRS assumptions were developed using data from Office of Financial Management (OFM), Washington State Patrol, and Department of Retirement Systems. TRS and SERS assumptions were informed by input from Senate, House, and OFM staff.
These Fund Split assumptions were most recently reviewed during the 2022 Legislative Interim. This table should not be used to reflect actual obligations for any funding source. We use long-term assumptions to produce our short-term budget impacts. Therefore, our short-term budget impacts will likely vary from estimates produced from other short-term budget models.
5. Methodology
Plan 3 Total Allocation Portfolio (TAP) Annuities
The Projections Model includes assets, benefit payments, and liabilities for Plan 3 TAP annuities that have been purchased by members. The model does not forecast future purchases of Plan 3 TAP annuities.
Approach to UAAL in LEOFF 1 Retirement Plan
As of the most recent AVR, LEOFF Plan 1 does not have any unfunded liabilities so contributions to the plan are not required under current law. If UAAL had emerged then it was intended to be amortized by June 30, 2024.
A LEOFF 1 UAAL can occur beyond June 30, 2024 under our stochastic projections. When this occurs within the model, we assume the UAAL will be amortized, through contributions from the GF-S exclusively, over a ten-year rolling period of total LEOFF retirement system salary. This assumed funding method is similar to the current funding method for PERS 1 and TRS 1 except we do not assume a minimum contribution rate for LEOFF 1.
Comments on Projections Model
As required under ASOP 56 - Modeling, we share comments in the 2024 AVR related to our reliance on the ProVal® software developed by Winklevoss Technologies. Please see the 2024 AVR for disclosures related to the software created by an external source.
Using Microsoft Excel, our office created a Projections Model for developing measurements as of a future point in time. The model relies on output from ProVal software as well as assumptions, methods, data, and assets disclosed on this webpage. The output was reviewed for reasonableness by comparing results to simplified estimates done in Microsoft Excel. A limitation of our deterministic Projections Model is if experience is materially different from our expectations. Stochastic analysis can be run in the Projections Model to demonstrate how the investment experience can deviate from our expectations; however, the model does not perform analysis on potential changes in demographic experience.