'Potential error' delays GDP data - (or... that must be wrong!)

Every traider hangs on the release of data. They live and traid on data.

Is it paranoia to think that the delay of the publication of GDP figures be because they are not quite what was expected?

Are they sensitive due to the fragility of the markets maybe?

A "potential error" has forced the Office for National Statistics (ONS) to delay the publication of the latest GDP figures, due on Wednesday.

The very rare move was caused by concerns over the reliability of some of the figures, the ONS said.

news.bbc.co.uk...

It would be interesting to know what kind of error this is.

Are they including WalMart in the GDP these days? How does the GDP count products of American companies made offshore? Does anyone know offhand?