Data for the Monthly Services Index (MSI) is collected each month from a sample of 2,250 enterprises. Information on the Retail and Motor Trade sectors is taken from the Retail Sales Index sample of approximately 1,600 enterprises. The Monthly Services Value Index (MSI) monitors trends in output at current prices of enterprises in the non-financial traded services sector and covers services provided by businesses both to individual consumers and to other businesses.
Despite the current difficult circumstances, many enterprises have continued to supply us with this information on a monthly basis and we wish to thank all survey respondents for their ongoing support. The response rate for the September 2020 MSI was similar to the corresponding month last year. The provisional index for each month is subject to revision in the following month as additional information from late respondents is obtained.
The Monthly Services index is based on a matched sample of enterprises in consecutive months. Imputation is not normally carried out for smaller enterprises which have not returned data. In each sector several key companies are identified based on their significance to the sector (turnover). If key company data is not received on time for the Provisional results, an estimate is derived for the current month using trends shown by responding enterprises in the same sector and, in certain cases, through the use of auxiliary data sources.
These auxiliary data sources were also used to validate the results for September 2020 at sectoral level. The CSO is satisfied that this range of auxiliary information supports the trends shown in the Monthly Services Index for September.
The auxiliary sources used for imputation and validation purposes included:
The patterns since March 2020 have been an exception to the existing seasonal patterns. Seasonally adjusting the Monthly Services Index will continue to be challenging until the scale and shape of the COVID-19 impact on the time series is better understood. The seasonal adjustment models were reviewed each month since March and have been changed as appropriate. Users should be aware that further observations, as data becomes available in the months ahead, and revisions to the seasonal adjustment models may result in revisions to the seasonally adjusted series.
The CSO wishes to thank all those enterprises who supplied their turnover data for September and urge them to continue to do so for October and future months. Even if turnover is nil or very low, such information is still needed to measure the trends in the services sector. The CSO will continue to monitor the range of supplementary information described above to derive the best estimate for services turnover in October. The October Monthly Services Index is planned for publication on 8th December.