Tim Lloyd is Professor of Economics in the Business School here at ֱ. Following the EU referendum, he was commissioned by the UK Government to take on a confidential project to assess the impact of Brexit on food prices in Britain.
Trusted by Government
“I’d worked with the Department for Environment, Food & Rural Affairs (DEFRA) a number of times since the late 1990s. As a result, I’d built a relationship with DEFRA officials and a lot of trust. They knew me and my work, so when the research team, led by Steve McCorriston at Exeter University, pitched for the food prices project, we were well known to them. We still had to think hard about the underlying mechanisms and develop a winning bid to secure the grant funding but at least the relationship we had built up gave us a good understanding of what DEFRA officials were looking for in a project of this sort.
What was a bit of a surprise about this project was just how sensitive it was. For the research team, it was another modelling exercise that would hopefully deliver useful analysis and evidence to inform policy making – but for the Government it was politically very sensitive. The messaging around food prices always needs careful handling but add Brexit to the mix and you have a real hot potato! So, everything had to be confidential, and for a long time we weren’t even able to acknowledge the existence of the project, let alone publicise results or the impact the project was having. This posed a problem in terms of gathering evidence for the impact case study we planned to submit to the REF2021. Thankfully, senior officials, including the Chief Economist at DEFRA, were willing to write testimonials which we submitted as key sources of evidence.
A unique piece of work
Once the econometric modelling was completed, we developed a new interface tool, called STEFI, which was unlike anything we’d done before. This new tool was designed to allow analysts at DEFRA to simulate how food prices here in the UK might change following the loss of free trade with Europe, as well as the potential for free trade agreements with other countries.
Half of our food in the UK was imported, and half of that was from Europe. So, any changes in trading arrangements would certainly have consequences for the price of food. Some products would become more expensive and some might even become cheaper. Importantly, DEFRA ultimately wanted to understand what this would mean for UK shoppers, especially those on low incomes who would feel the impact of any price rises most acutely. STEFI allowed us to provide those answers for a wide range of potential trading scenarios.
Department for Environment, Food & Rural Affairs
It is impossible to overemphasise the enormous contribution that your work in developing STEFI, as leading experts in your field, has made to DEFRA’s capacity.
Our impact
We know that DEFRA used the pricing project results to deliver briefings to ministers and to inform trade negotiations. The Secretary of State referenced the work in Parliament, and in broadcast media, when responding to concerns about rising food prices. Details of these were cited in the testimonials provided by DEFRA to the REF2021. We also know our work went beyond DEFRA too, to other departments involved in the Brexit negotiations.
Since that time STEFI has been repurposed to model the impact of Covid and the invasion of Ukraine on food prices. With an eye on future challenges, DEFRA has commissioned the project team to update and develop the functionality of STEFI to include the health as well as price impacts of trade and other emerging shocks, such as weather-related climate change. An Early Career Researcher based at ֱ has also joined the project team for this work, which will continue into 2026. Hopefully, this will be a useful platform for his career too.
The modelling that underlies STEFI is quite sophisticated, but the interface itself is designed to be easy to use so that DEFRA analysts can use it on an everyday basis without our help. Policymakers need to have information at their fingertips to allow them to respond rapidly and make evidence-based policy.”