The writer is a Labour MP and a member of the Treasury select committee
One of the first lessons I learnt at the Financial Times was about the communication of numbers. Don’t describe a number to a greater degree of accuracy than you can guarantee. If you eyeball a football stadium, and estimate it’s roughly half-empty, you should describe this as “half”, not “50 per cent”; the latter misleadingly suggests accuracy to within 1 per cent.
The UK collectively forgets this lesson every six months or so, whenever the Office for Budget Responsibility publishes its fiscal outlook. Despite the best efforts of the OBR to inform us about probability bands and uncertainty, we remain unduly focused on a single point estimate.
The OBR is mandated to forecast fiscal headroom, which is the difference between UK tax revenues and government spending, four years out from now. These are two fairly uncertain and very large numbers; it’s no wonder the result fluctuates.
Projected headroom can vary substantially even within one month. Between October 3 and October 31, in the three rounds of “pre-measures” forecasts which the OBR carries out to incorporate new data between each round, it changed by £6.7bn.
Between every six-month forecast, the OBR’s average change in headroom is £21bn — and this is before they start assessing any difference in government policy. That’s almost the same as this government’s actual headroom, which chancellor Rachel Reeves wisely raised to its highest level since Boris Johnson was prime minister. It’s also more than the amount the NHS spends on primary care per year.
I find it difficult to explain to my constituents a system that links whether one can see a GP promptly to a highly uncertain set of economic forecasts. Hence the rise of populists with easy answers who are willing to pull the whole system down.
The OBR is an important institution but it is not being deployed to its full potential. More focus should be put on its long-term sustainability forecasts, which it releases each summer. A simpler process would reduce the number of forecast rounds; this would remove the repeated fiscal fine-tuning in the weeks before a budget. For the same reason, Reeves is also right to cut the number of assessments to one per year. The House of Lords Economic Affairs Committee is currently conducting an inquiry into the UK’s fiscal framework. Economists giving evidence to the committee have raised broader concerns with the current framework, including its short-termism.
The political and media focus on point estimates of headroom risks missing the fiscal forest for the trees: the UK’s public finances are no more sustainable than they were before the creation of the OBR in 2010; the agency says as much in its own annual reports on long-term debt sustainability. Indeed, as British citizens live for longer but in poorer health, our public finances are getting worse.
Gilt market investors are much less bothered about headroom than the rest of us. As Peder Beck-Friis of Pimco told the Treasury committee, “I don’t think we will be overly focused on what the deficit will be in 2029 . . . the uncertainty band around that number is so high.”
Other fund managers have told me that it is unwise to focus on the headroom against any particular set of fiscal rules: after all, they invest in a range of countries’ sovereign debt with different rules. Instead, gilt market participants look at the total supply of gilts, the long-term deficit profile and the national growth trajectory. They may consider a range of forecasts, and compare the differences between them. Above all, their investments are anchored by the central bank’s policy rate, which depends on inflation.
That is a much more comprehensive view, which the government can learn from. The Budget measures that will have the most impact on decreasing the interest on debt were not just raising headroom, but lowering the cost of living, and thus giving the Bank of England more room to lower rates. The BoE predicts the chancellor’s cutting of energy bills and freeze in rail fares and fuel duty will decrease inflation by up to 0.5 per cent in the next financial year.
To improve our fiscal framework, we should return to the question of what its aims are. The UK government requires the confidence of international bond market investors. We need to make sure taxpayers’ money is not being spent on ballooning interest costs. And we sorely need to invest in our country’s lagging physical and human capital, which leaves us at a disadvantage compared to our peers. In short, we need a fiscal framework that keeps interest payments low and growth high.
