Data for the monthly Goods Exports and Imports is collected monthly from trading enterprises through the Intrastat survey and the Single Administrative documents (customs forms). Despite the current difficult circumstances, many retailers have continued to supply us with this information and we wish to thank all survey respondents for their support.
However, due to temporary closure and the difficulties faced by businesses, the response rates for Intrastat for recent provisional Goods Exports and Imports release were lower than would normally be the case. The response rate for May was 83% of the total value of trade, this would normally be around 89% for the preliminary monthly results.
We have modified our estimation process to account for the effect of COVID-19 on trading patterns by using data from traders who responded in concurrent months to feed into the estimation model for non-respondents.
Changes to the seasonal adjustment methodology used were incorporated from the April 2020 release. The seasonally adjusted data have been revised back to January 2010.
The previous X-11 methodology, developed by the US Census Bureau, has now been replaced by X-13-ARIMA implemented in JDEMETRA+. This is in line with Eurostat recommendations and guidelines. X-13-ARIMA has advanced modelling capability for the issues commonly faced in seasonal adjustment, and produces sophisticated diagnostics to help improve data quality.