Key economists and institutions highlighting the impossibility of a definitive, exact figure include:
- Dr. Graham Gudgin (Centre for Business Research, University of Cambridge): He has repeatedly argued that backward-looking estimates rely heavily on flawed "doppelganger" or synthetic counterfactual models (comparing the UK to a basket of other economies). He points out that the G7 average has tracked similarly to the UK since 2016, and argues that more time and patience are needed to strip out confounding factors like Covid-19 and the energy crisis to make an accurate assessment. [1, 2, 3]
- Catherine McBride (Trade Economist, Free Trade Expert): A vocal critic of mainstream consensus, she argues that attempts to quantify the exact cost of Brexit often conflate the withdrawal itself with domestic policies (like high taxes or energy costs). She notes that predicting what would have happened to UK trade if the country had remained in the single market relies heavily on assumption-driven models rather than solid, observable data. [1, 2]
- The Centre for Economic Policy Research (CEPR): In their meta-analysis of multiple Brexit studies, they concluded that wildly conflicting projections (ranging from small advantages to marked losses) are largely the result of the different methods, assumptions, and varying coverage of effects chosen by individual researchers. Forward-looking studies inherently struggle to factor in potential positive aspects of long-term economic integration. [1]
- The Office for Budget Responsibility (OBR): While the OBR and the Bank of England have published estimates—such as a roughly 4% reduction in productivity—they openly acknowledge this is just a "simple average" of highly reputable studies. They stress that long-run forecasting cannot give precise estimates of the effect of Brexit on GDP due to the sheer volume of unpredictable variables. [1, 2]
The core issue is that isolating the Brexit variable from other massive global shocks (e.g., the Covid-19 pandemic, Russian energy crises, and general inflation) requires creating a "counterfactual"—a hypothetical economic model of what the UK would look like today without leaving the EU. Because different economic models weight external factors differently, they produce widely varying figures, leading these economists to conclude that a perfect, universally agreed-upon number does not exist. [
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There you are, Alan. I think these names trump Rachel Reeves, albeit they probably know nothing about handling customer complaints in a retail bank
England
USA
