LONDON — The British government outlined the central argument on Monday it hopes will persuade voters to stay in the European Union, publishing a detailed economic analysis finding that Britons will be poorer if they quit.

The release of the publication by the Treasury, complete with complex algebraic calculations, is an important moment before a referendum, to take place June 23, on whether Britain should end more than four decades of integration and quit the 28-nation bloc.

Those who oppose a British withdrawal from the European Union, known as “Brexit,” say that it would inevitably lead to economic uncertainty and deter investment, and that it could complicate ties with the bloc, the country’s biggest trade partner.

On Monday, the government put a number on that claim, asserting that, under one midrange situation, annual economic output would be 4,300 pounds, around $6,100, lower per household if Britain left than if it stayed in the bloc.