The UK Actuarial Profession's Continuous Mortality Investigation (CMI) has released the latest version of its mortality projections model, "CMI_2024". This model, used by most defined benefit (DB) pension schemes when setting assumptions, projects the path for future mortality rates.
Life expectancy trends (compared with last year's model):
Impact on schemes (compared with last year's model):
The overall effect on pension schemes will vary based on the age profile of their members. Generally, adopting CMI_2024 over CMI_2023 will increase scheme liabilities by around 1%.
In addition to the inclusion of data from England and Wales for 2024, CMI 2024 also includes significant model changes:
2024 saw the lowest mortality rates on record for England and Wales, lower than 2019, prior to the pandemic. After a prolonged slowdown in population mortality rate improvements since 2011 followed by the COVID-19 pandemic, this overall more positive outlook in CMI 2024 ends the trend of declining life expectancies in successive model iterations.
While older adults see improved life expectancies, mortality for those under 45 remains at a higher level than observed in the early 2010s. The model's more optimistic outlook for older members contrasts with a less favourable view for younger ones.
Adopting CMI 2024 may slightly increase liabilities for DB pension schemes. However, for triennial actuarial valuations this year, which may have last used the CMI 2021 model, liabilities could still decrease. Despite returning to pre-pandemic levels, mortality rates are still higher than expected based on pre-pandemic projections.
Schemes eyeing near-term buy-ins or buyouts will closely watch how insurers adapt their models, as they often incorporate new data points more swiftly.
The CMI 2024 model also includes several other more minor technical enhancements.
The table below shows the percentage change in life expectancy from CMI_2023, which varies across the age range.
| Male | Female | |
|---|---|---|
| Age 25 | -0.12% | -0.11% |
| Age 45 | +0.07% | -0.14% |
| Age 65 | +1.25% | +0.14% |
| Age 75 | +1.77% | +0.70% |
| Age 85 | +2.51% | +1.46% |
Note: Life expectancy changes are at 1 January 2025 based on typical base mortality tables, projected from 1 January 2017 with core model parameters and a long-term improvement rate of 1.5% pa.