Let's not get too worked up about the £40 billion loss by RBS - those foolish bankers that went into a bidding war to buy ABN Amro at peak.

If the Nationwide figures are any reflection of the true value of houses in the UK then we have just witness about £1 trillion wiped off the value of the nation's housing stock in the same time it has taken for the full lunacy of the ABN Amro deal to be realised.

We certainly hope the full lunacy has been realised.

The latest house price figures from Nationwide step smartly on a large bunch of those few delicate green shoots spotted in the economic garden.

A further drop in February of 1.8% means that house are on average worth more than 20% less than they were at peak in October 2007, just when the champagne corks were popping in the flash new RBS headquarters in Gogarburn.

(I was amused to see the press release welcoming the opening of those new offices with the health warning "This item was published during the term of a previous administration that ended in April 2007" at the head of the page. I wonder would it be the same if the bank was still flying high? Still I digress.)

So the average house on the Nationwide measure is worth about £147,746 against the £186,044 in October 2007. That's a drop of £38,300. Which if projected across the 26.5 million or so homes in the land that comes to more than £1 trillion.

OK you might quibble and want to take off a bit for the poor state of some of the 2.6 million local authority housing stock. But we could also quibble about the actual price Nationwide puts on the average house - lower for instance than the Halifax average.

So the trillion pound figure - give or take a couple of RBS losses - is probably about right, given that the national statistics put the total value of housing stock outside the public sector at £4,077 billion.

I am not sure if that makes you feel any better about the RBS £40 billion financial fiasco or not. Probably not.

But we live in rather surreal times and the picture has been getting a lot more wobbly as we have breakfasted on the latest batch of news.