Marcus Ashworth & Stuart Trow, Columnists

British Taxes Are About to Get Very Complicated

No capital.

Photographer: Chris J. Ratcliffe/Bloomberg

Economists might tell you otherwise, but it’s impossible to model how a £3 trillion ($4 trillion) economy will react when you start messing around too much with things like taxation. Chancellor of the Exchequer Rachel Reeves is yet to learn this.

When she stands up to deliver her second UK budget on Wednesday, this habitual tinkerer will lay out a raft of revenue increases that has been tested to the max by the British Treasury’s sophisticated econometric tools. These models provide precise estimates of the impact of tax, spending and borrowing policies on the economy.