CMI Working Paper 55 accompanies the updated version of the CMI Mortality Projections Model, CMI_2011, and is issued alongside the model and an updated user guide

The structure of the CMI_2011 model is identical to that of the previous versions. However, the default parameters contained in the model have been updated to reflect the publication of England and Wales population mortality data for calendar year 2010. This working paper illustrates the impact of incorporating data for 2010.

The Committee has changed its process of working with the population data published by the ONS

To allow earlier release of the updated model, the CMI now seeks to mirror the calculation algorithm used by the ONS to produce high-age population estimates rather than waiting for the ONS to publish that part of the required data. Any loss of accuracy from this approach is expected to be minimal and to be considerably outweighed by the benefits of releasing the model earlier. Further details of this change of process are set out in CMI Working Paper 54.

The default initial rates of mortality improvement are higher than those published in CMI_2010 at the youngest and oldest ages, for both males and females, but the comparison is more complex between ages 40 and 90 with estimates higher at some ages and lower at others

Accordingly core projections generated by the CMI_2011 model produce expectations of life which are generally slightly lower than those produced by CMI_2010 (with other parameters held constant) for males, and slightly higher for females.

Download the latest version of the Model, CMI_2016.

The previous versions of the CMI Mortality Projections Model can be accessed as follows:

  • CMI_2010 and its user guide can be accessed via CMI Working Paper 49.
  • CMI_2009, its user guide and an Excel spreadsheet containing additional results for the parameter sensitivity tests, as described in the user guide, can be accessed via CMI Working Paper 41.

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