London homeowners are likely to be surprised to discover that their property has typically plummeted in value by £27,000 in just one month - partly, it seems, because government statisticians overstated the strength of the housing market in January.

The Office for National Statistics (ONS) has wiped thousands of pounds off the value of UK homes after carrying out a revision of its data. At first glance it appears that the ONS massively overestimated the rate of house-price growth, but the government department rejects this suggestion, saying it has merely updated its house price index.

The original ONS data, issued last month, prompted the Guardian to report that property prices in London were increasing by almost £500 a day. It now appears this was not the case.

The revelation that the ONS has dramatically revised its numbers is discreetly tucked away in the department’s latest monthly house price index. Last month the ONS declared that the average London house price hit a record high of £551,000 in January. That was £15,000 up on December’s figure of £536,000. But the latest figures state that the average London house price in February was £524,000. This figure is £12,000 down on December 2015 and £27,000 lower than the figure declared for January.