Opening his quarterly press conference today the Governor of the Bank of England, Mark Carney, said the response of British households to the Brexit vote had essentially been to shrug their shoulders and carry on spending.

This surprised the Bank, which had expected households to tighten their belts in response to the uncertainty generated by the result.

Yet, as Carney also noted, the financial markets’ response to the referendum result has been “less sanguine”.

He can say that again.

Sterling has lost almost a fifth of its value against the dollar since the referendum.

And the volatility of the UK’s currency has been as gut-churning as the twists on an Alton Towers roller coaster.

Sterling has become easily the most significant financial barometer of fluctuating market sentiment on the UK’s post-Brexit prospects.

The pound was up today by as much as 1.4 per cent in the wake of the High Court verdict that the Government cannot bypass Parliament in invoking the Article 50 EU divorce proceedings.

This was the pound’s strongest intra-day rise since July – a good day for sterling after a month (October) in which it was the worst performing currency against the dollar in the world.

Why are currency traders so excited?

Is it because they think Brexit won’t now happen?

Some probably do.

Deutsche Bank economists have today predicted that Theresa May will be forced into calling another general election next year.

If she loses, the next Prime Minister and Government, conceivably, might not want to leave the EU.

Or maybe the whole process will be slowed down, giving time for the British people to change their mind.

Some legal experts have suggested that there is little chance of Article 50 being invoked by next March as May previously promised.

More traders probably think there is a higher chance of a softer Brexit, that Remain-minded MPs will somehow be able to rein in the hardline Brexiteer ministers such as Liam Fox and David Davis and perhaps keep Britain in the single market.

Are they right?

The rationality of the financial market should not be exaggerated – nor should their knowledge of politics.

As The Independent’s veteran political expert Andy Grice says, any traders betting on Brexit not now happening are likely to lose money.

There’s a huge amount of mindless momentum trading in currency markets.

A piece of news is bad for the Government’s Brexit plan? Sterling goes up – and everyone piles in behind in anticipation of a quick profit.

A signal of hard Brexit from ministers? Sterling goes down – and everyone piles in again for the same reason.

Until the next piece of news breaks the trend.

Politically and analytically sophisticated the process is not.

What does the falling pound mean for you?

Daily moves should not be treated too seriously.

Yet broader shifts and patterns do merit our attention.

The Bank of England today made it very clear that it thinks the major downshift in the UK exchange rate since June reflects a “perceived supply shock” to the British economy.

In other words, the feeling that Britain will be made permanently poorer by the Brexit vote and what follows.

Perhaps they are wrong. Markets sometimes are. And many Brexiteers say so.

But the independent economic experts at the Bank of England don’t think so.

We will find out on 23 November in the Autumn Statement whether the independent economic experts at the Office for Budget Responsibility are similarly pessimistic.