HM Land Registry versus Nationwide House Price Indices

HM Land Registry's April figures published today (end of May!) show:
average price £183,626; monthly price-fall 0.2%; and annual increase 2.7%.

As Growler at HPC points out, this is much the same as the Nationwide's February figures:
average price £179,358; monthly price-fall 0.5%; annual increase 2.7%.

To check this, let's compare HM Land Registry's January figures:
average price £186,045; monthly increase 0.9%; annual increase 6.4%; with Nationwide's November 2007 figures:
average price £184,099; monthly price-fall 0.8%; annual increase 6.9%.

Going back a further three months (just to be absolutely sure); HM Land Registry's October 2007 figures:
average price £184,346; monthly increase 0.1%; annual increase 8.1%.
Nationwide's August 2007 figures:
average price £183,898; monthly increase 0.6%; annual increase 9.6%.

Yup, by and large, this is just a time lag thing. Nationwide publishes the month's selling prices at the end of the month; HM Land Registry then takes two months to update their register. And then takes a further month to publish them.

There must be some messing about with seasonal adjustments - HMLR's average price has fallen by £720 over six months, but Nationwide's by £4,540. The monthly changes are all over the place, of course, but the year-on-year change is pretty much the same for either index, and that's the most important statistic.