Cue rolling television coverage and special editions of all the newspapers.

It's all great theatre, but in market terms the budget is usually a total non-event.

The average movements in the stock market,

in the exchange rate and in the government bond yield on budget days

are barely any different from the movements on any other day of the year.

But this year, it would be unwise to switch off from post-budget coverage altogether.

And the reason for that is that, like everything else in British politics,

budgets must now be viewed through the prism of Brexit.

Philip Hammond's main objective with this year's Budget was not to get sacked.

A weak affair might have hastened his departure, and that would be bad news for sterling,

because investors like Mr. Hammond's perceived pragmatism.

He favours a gentler version of Brexit and is a vocal backer of City interests in Europe.

If he went, it is likely he would be replaced with a more skeptical minister.

Brexit-favouring Michael Gove is the bookmakers' favourite.

Backroom manoeuvring over the budget

is seldom evidenced on the day of the speech itself.

Mr Hammond was, of course, cheered to the rafters by his own MPs.

Budgets usually unravel in the days after,

like George Osborne's infamous "omnishambles" in 2012.

Signs to watch out for include negative stories in the rightwing press,

sniping comments from anonymous colleagues, and worst of all,

budget measures that attract their own uncomplimentary monikers.

A 2017 equivalent of 2012's "granny tax" would surely be a cue to sell the pound.