Professor Aditya Goenka explains why the Chancellor’s decision to accept a reduced fiscal headroom is preferable to mechanically restoring the buffer.
In response to the UK government's Autumn Budget, Professor Aditya Goenka said:
“The Chancellor’s decision to accept a reduced fiscal headroom of £15 billion down from almost £24 billion in March is preferable to mechanically restoring the buffer. The Budget’s forecast decomposition identifies higher debt-interest costs as the dominant source of fiscal deterioration. Meanwhile, OBR’s downgrade of 2027 growth from 1.6% to 1.0% would have made additional tightening particularly risky if implemented during the slowdown.
“Fiscal tightening to restore the headroom could compound economic weakness without addressing the external pressures raising debt-servicing costs. Although borrowing is higher than forecast in March, the OBR still projects it falling from 4.2% of GDP in 2026–27 to 1.8% in 2031–32. The credibility of that trajectory matters more than mechanically defending the previous headroom figure.
“The previous Chancellor, Rachel Reeves, changed the fiscal rules to distinguish investment from day-to-day spending and recognise a broader range of financial assets. But she retained the underlying dependence on forecast outcomes in a particular year, leaving fiscal policy vulnerable to repeated adjustments as those forecasts change.
“My parliamentary evidence and research explain how rigid rules can generate self-fulfilling fluctuations: the gilt markets react to announcement of changes in fiscal outlook and anticipate a fiscal response; expected tightening depresses spending and investment, weakens revenues and makes tightening more likely.
“External shocks such as commodity-price shocks associated with Ukraine and Iran should not automatically trigger domestic policies that amplify their effects. The modest initial fall in gilt yields today suggests markets accommodated the smaller buffer, although it was anticipated.
“For the UK economy, using a larger headroom can cushion economic weakness. However, lasting credibility depends on realistic, deliverable spending plans, productive investment and a sustainable medium-term deficit trajectory—not mechanically defending a fragile forecast number against shocks beyond the government’s control. Thus, this may prove to be a move towards a more sustainable fiscal regime in UK.”
For more information and media inquiries, please contact Ellie Hail (e.hail@bham.ac.uk), Communications Officer, University of Birmingham, on +44 (0)7966 311 409. Out-of-hours, please call +44 (0) 121 414 2772.
Chair in Economics
Professor Goenka specialises in economics and research on innovation, risk, and global economic policy.
