Major Time Series Analysis Caveats
Further Education (FE) Colleges were reclassified as Central Government entities on 13 October 2010, transferring FE Colleges from the private/business sector to the public sector. This change brings FE Colleges out with scope of ABS survey from 2010 onwards, which represents a step change in the 2010 results for SIC 85 compared to data for earlier years.
The data, from 2008 onwards, are published on a Standard Industrial Classification (SIC) 2007 basis – data pre-2008 were published on a SIC 2003 basis. Updates to the SIC are required to enable it to more accurately reflect the structure of the modern economy - SIC 2003 was replaced by SIC 2007 in January 2008. The revision was motivated by the need to adapt the classification to changes in the world economy. The revised classification reflects the growing importance of service activities in economies over the last fifteen years, mainly due to the developments in information and communications technologies.
More information on SIC (2007) is available at: http://www.scotland.gov.uk/Topics/Statistics/Browse/Business/Corporate/sic2007note#top and http://www.ons.gov.uk/ons/guide-method/classifications/current-standard-classifications/standard-industrial-classification/index.html
The employee/employment data published in SABS, from 2008 onwards, are based on Business Register and Employment Survey (BRES) – previous years SABS employee data were based on the employment part of the Annual Business Inquiry (ABI/1). The BRES replaced and integrated the Business Register Survey (BRS) and the ABI/1 in 2009 (note that there was a pilot of BRES in 2008 which allowed 2008 BRES estimates to be produced). For businesses that are surveyed by BRES, the regional and local estimates of employment are more accurate (than those from the ABI/1) because, rather than producing data by a headquarter-based apportionment model, they are obtained directly from data reported at site level (shop, office, factory, etc). More information on BRES is available on the ONS website at: http://www.ons.gov.uk/ons/publications/all-releases.html?definition=tcm:77-230512
The 2008 and 2009 ABS followed a similar sample selection criteria (see Sample Design section below) and were both sampled on a SIC 2007 basis. It is important to note that 2009 marked the full introduction of the BRES, this and the change to SIC 2007 may lead to some discontinuity with businesses moving from one SIC to another between years. It is not unusual for some businesses to change SIC code over time, but there are some particular movements between 2008 and 2009 that users should be aware of e.g. a large number of landscape business sites have moved from SIC 01 (Crop and animal production, hunting and related service activities) to SIC 81 (Services to Building and Landscape Activities) between 2008 and 2009 – this is a result of the change from SIC03 (where landscape businesses were included with the agricultural sectors) to SIC07 (where landscape businesses fall under the services sector).
Insurance and Reinsurance (SIC 65.1 and 65.2) data is published for 2008 onwards – this is the first time that these data have been included in SABS. Please note that SIC 65.3 (Pension funding) is still omitted from the SABS results.
ONS improved the sample design for the 2008 survey which means that the results for 2008 onwards cannot be compared with historical trends. Although this temporary loss of comparability over time is a downside - it means that the results for 2008 onwards are more accurate, and comparisons can still be made between sectors across the UK. More details are provided below on the change in sample design due to SIC 2007 and the complete re-allocation of the sample.
Notwithstanding, the change in sampling, the high energy prices in 2008 have had a significant impact on the "Remaining Sectors" results for Scotland in 2008.
For 1998-2005 data, Scottish Government analysts merged ABI/1 (employment survey) and ABI/2 (financial survey) results in order to produce consistent "per employee" totals (e.g. GVA per employee). During this process, employee data was retained only if a company was part of smaller financial survey. However, for 2006-07, there was a change in the sampling arrangements for the two parts of the ABI. In previous years, ABI/2 was a sub-sample of ABI/1 but they moved to being sampled separately in different months. This led to non-matching between the two sets of results - affecting around 3-4% of total ABI/2 units. For these units, employee totals were set to their values from the Inter-Departmental Business Register (IDBR).
Further, for 2006-07, ABI/1 survey reference date moved from December to September. This step change should be taken into consideration when analysing time series data.
From 2001 coverage of Section A (on SIC 2003 basis) was further extended to include Groups 01.4 (Agricultural and animal husbandry service activities, except veterinary activities; landscape gardening) and 01.5 (Hunting, trapping and game propagation including related service activities). Within Groups 01.4 and 01.5 employee data is volatile between years due to small sample size - time series should therefore be treated with caution.
From 2000 ABI coverage (on SIC 2003 basis) was extended to include Division 02 of Section A (Forestry, Logging and Related Service Activities) and Division 05 in Section B (Fishing).
From 1999 improvements to the questionnaires for Sections M (Education - excludes some public sector) and N (Health and social work - excludes some public sector), both on SIC 2003 basis, led to a movement of data from 'total turnover' to 'value of grants/donations received'. This caused the approximate Gross Value Added at basic prices to fall between 1998 and 1999.