Three of the UK’s leading pensions consultancies have warned that uncertainty over the way defined-benefit (DB) pension plan sponsors should set their inflation and mortality assumptions under International Accounting Standard 19, Employee Benefits (IAS 19), could lead to substantial diversity in practice this year-end.

In particular, sponsors are reportedly struggling with whether they should factor in the UK government’s announcement on 4 September over plans to consult on a move from the Retail Prices Index to the Consumer Prices Index as the basis for measuring inflation.

IPE has also learned there is similar uncertainty over the transition adjustment from the Continuous Mortality Investigation 2017 to the latest 2018 model.

Lane Clark Peacock partner Alex Waite said: “Some people take the announcement as implying that RPI will no longer exist in its current form in a decade’s time and we will effectively all use CPI. Alternatively, there is another view that nothing really changed on 4 September.”

Sparking the uncertainty is the news that the UK government plans to consult next year on proposals either to slight RPI with CPIH at some point between 2025 and 2030 or leave the matter to 2030 when the UK Statistics Authority can take the decision on its own account.

The government move follows the publication in January of a House of Lords Economic Affairs Committee report, Measuring Inflation, addressing the future of RPI.

Andrew Mandley, a UK IAS 19 specialist with Willis Towers Watson, added: “The big issue to watch for is whether companies reduce the assumed gap between RPI and CPI for this year end.

“The numbers we are talking about in the accounts are potentially very big numbers”

Simon Robinson, consultant actuary at Deloitte

“Looking at the 30 September accounts we have seen so far, some companies have stuck with a 1% difference, but others have reduced it to a 0.8% gap. I expect we will see a similar pattern in the year-end reports, too.”

In terms of the financial impact, Mandley said it all depends on “how much of your pension liability is linked to each of RPI and CPI inflation. But if you think about a 0.2% change in inflation assumptions, potentially you could be talking 2-4% of the DBO.”

Simon Robinson, a consultant actuary with Deloitte, added: “The numbers we are talking about in the accounts are potentially very big numbers and could be as extreme as a reduction of 20% of the gross liability.”

He also warned that a sponsor with a net asset position of £100m could end up in a deficit situation simply if they had hedged their inflation exposure because of the impact of the change on the asset side.

On the issue of diversity in practice, LCP partner Tim Marklew told IPE: “The FRC hasn’t opined on any particular course of action.

“We have sat down with all the major auditors and they have slightly different views. Some are quite conservative and their approach is to carry on as before, and others see the September announcement as a reason for firms to re-evaluate how they set inflation assumptions.”

Meanwhile, it has emerged that it is unclear whether DB sponsors will uniformly adopt a so-called initial addition to the CMI 2018 to reflect the fact that those with access to DB provision tend to lead more affluent lifestyles than the wider population on average.

Mandley said: “The introduction of the CMI 2018 has meant changes to some of the parameters underlying that model. In particular, less smoothing of the downturn in the rate of mortality improvement this decade produces lower life expectancy figures than in previous version, CMI 2017. On it’s own this could reduce the calculated DBO by 1% to 3%.”

“The FRC hasn’t opined on any particular course of action”

Tim Marklew, partner at LCP

He explained that those sponsors that opt to include the new initial addition “could find that there is little change to their overall mortality outcome and hence little change to their DBO.”

In a statement addressing both inflation and mortality assumptions, an FRC spokesperson told IPE: “The two matters you raise are technical issues relating to Defined Benefit pension provision which do not come under the supervision of the FRC.”