ABI sample coverage

Details of Annual Business Inquiry sample coverage.

The Northern Ireland Annual Business Inquiry (NIABI) collects both financial and employment information from businesses and other establishments and covers about two thirds of the economy.

Inclusions and exclusions

This includes the production, construction, distribution and service industries in Northern Ireland but excludes public sector activity for the most part. Coverage also includes agriculture (support activities), hunting, forestry and fishing.

Along with those exclusions stated above, the other main areas that are excluded are public administration and defence (section 0) while agriculture, forestry and fishing (section A) excludes farming (groups 01.1, 01.2, 01.3, 01.4 and 01.5).  Local authority and central government bodies in education (section P) and human health and social work activities (section Q) have also been excluded from this publication, as has 86.2 (medical and dental practice activities) within section Q. 

Sampling frame

The Inter Departmental Business Register (IDBR) is the sampling frame used for the NIABI.  The register consists of companies, partnerships, sole proprietors, public authorities, central government departments, local authorities and non-profit making bodies in the UK.

The UK Standard Industrial Classification of Economic Activities 2007 (SIC 2007) sections covered by the 2012 NIABI data are as follows:

A - Agriculture (support activities), forestry and fishing
B - Mining and quarrying
C - Manufacturing
D - Electricity, gas, steam and air conditioning supply
E - Water supply, sewerage, waste management and remediation activities
F - Construction
G - Wholesale and retail trade; repair of motor vehicles and motor cycles (Distribution Industries)
H -Transport and storage
I - Accommodation and food service activities
J - Information and communication
L - Real estate activities
M - Professional, scientific and technical activities
N Administrative and support service activities
P - Education (excludes local authority and central government bodies)
Q - Human health and social work activities (excludes local authority and central government, and medical and dental practice activities (group 86.2))
R - Arts, entertainment and recreation
S - Other service activities
Production industries  -comprised of sections B – E
Service industries - comprised of sections H, I, J, L, M, N, P, Q, R and S

To maximise survey precision, the Neyman allocation approach to sampling was utilised. The survey universe was stratified by 2 digit SIC code and employee size band, and all businesses with 50+ employees, or 20+ employees and more than one local unit, were fully enumerated.  Businesses falling below the threshold of complete enumeration are selected on a random stratified basis.