The construction industry in Europe is worth €1.545 trillion, employing 12.7 million workers.
According to Eurostat, the UK contributes €232,296.2 million to the sector. This computes to around 15%.
As a very rough estimate, then, if the UK contributes 15% to Europe's construction sector, as the top 100 UK firms earn $84,859 million in revenue, this means the top European firms could earn a total of $565,726 million. This would be for the top ~667 firms.
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