I have a question concerning the quantities in COMTRADE. We are working with the data taken from HS92 nomenclature for the 1995-2005 period.

We have calculated unit values (the ratio “values over quantities”) for all products, all years and some countries of interest (China, USA, European Union, etc) and we compared the results. We made some aggregations according to product segments. For the period 1995-2004, as we expected, we found the usual North-South differences, with some cases suggesting convergence, but always with great differences, and the series seem coherent in time.

But for the year 2005 we found unit values that are not reasonable, for example, with China having almost the same unit values than EU or USA. We searched for some causes behind this issue. We looked at trade values and we found nothing strange in data. So the remaining candidates are quantities, that could be reported with more measurement error (but recall that for the previous years unit values were reasonable).

I would like to ask if somebody has found a similar problem for 2005 data, specially in relation to quantities reported, and if you have isolated the source of the problem (some specific countries? some specific products?).

Thanks in advance