Try a few numbers from Nationwide to see why house prices have been rising faster, not slower, since the Bank of England started raising interest rates in August.

The average sum outstanding on a British mortgage at the end of last year was £85,500. Only 57 per cent were on variable rates - so 43 per cent were held by people who had prudently sheltered themselves. Home-buyers with the biggest loans were the most likely to go for fixed-rates.

Then, the 57 per cent with variable loans have not suffered too terribly. Average mortgage rates have risen 0.65 per cent since July - not the Bank's full 0.75 per cent because lenders are competing.

Nationwide says this added just £34 to the monthly payments of somebody with that average £85,500 mortgage. It would be pleasanter to have the money. But anybody who got, say, a three per cent pay increase on a £20,000 salary last winter still has a little left over - without a bonus.

Fine, but those are people who bought years ago. Recent buyers with mortgages taken out to meet recent prices must be looking at very different numbers. Some are - but fewer than you think. In February more than three-quarters of loans - including re-mortgages - started on fixed rates.

But the median mortgage had risen to £125,000. Yet even with that, the increase so far, for the 25 per cent on variable rates, has been under £50 a month, tiresome for those who pushed themselves to the limit to buy, but for the most part bearable.

In parts of the country there are people, not least buy-to-let landlords, who have taken on mortgages that make sense only if the price of the place they bought goes on rising faster than other prices. But there cannot be many of them in the West Midlands where house prices generally have done nothing much for two years.

Anyway, none of that is in the same world as the situation in the crisis year of 1990 when interest rates had pretty well doubled - quite unexpectedly - over the previous two years and 1.4 million people had lost their jobs.

Still, what happens next? Another quarter-point on interest rates next month is unwelcome to those without a fixed-rate deal. But it is not going to bring down the house of cards. Supposing, though, just supposing, that is not the end of it, that the worst-case scenario unwinds and the Bank piles on a full percentage point in the coming months. Well, lots of home-buyers would be paying 16.7 per cent more for their money than in July last year, enough to make a mess of many household budgets.

The music would stop, possibly with a bump. Fixed-rate deals are all very well, but many of them last for no more than two years. A good number were taken out at 4.99 per cent in the summer of 2005. Their holders are in for a shock shortly even if the Bank does nothing - although house prices could still go on climbing.