ONS trial finds its supermarket price analysis is not as accurate as thought

Food and drink prices have fallen in the UK faster than official inflation measure, according to a new, experimental version of measurement that the Office of National Statistics has trialled.
This experimental new version of measuring looks at prices advertised on the supermarket websites, and there was a discrepancy between the results of this new measure and the traditional one.
Between June 2014 and April 2015, the old method of analysis of 35 items fells by 2.5 per cent, but the new, online analysis, which made use of price comparison between three of the large supermarket chains in the country, reported a 6.7 per cent drop.
Of course, this has created the worry that the old methods that the Office of National Statistics is using are outdated and inaccurate.
With the move to online buying, which is slowly becoming a bigger and bigger part of the market, it makes sense that this needs to be brought into the equation.
It is surprising that the difference should be so large, seeing as these are figures that a lot is based off in terms of superstore comparison. However, it is good that the Office of National Statistics took it upon itself to undergo this test, showing that they are actively interested in honing their methods of analysis.