The Northern Ireland Index of Services (IOS) is an important short term measure of changes in the output of the private sector service industries within Northern Ireland.
The IOS is a quarterly sample survey of around 3,500 companies designed to provide a general measure of changes in the output of the Wholesale, retail, repair, Accommodation & food services; Transport, storage, information & communication; Business services and finance; Other services sectors. It is based on up-to-date information about the output and sales of the services industry. The Index is published quarterly in March, June, September and December of each year.
