The Enterprise (the top of the hierarchy), is associated with a complete set of financial statements. The enterprise, as a statistical unit, is defined as the organisational unit of a business that directs and controls the allocation of resources relating to its domestic operations, and for which consolidated financial and balance sheet accounts are maintained from which international transactions, an international investment position and a consolidated financial position for the unit can be derived. It corresponds to the institutional unit as defined for the System of National Accounts.

The Company is the level at which operating profit can be measured. The company, as a statistical unit, is defined as the organisational unit for which income and expenditure accounts and balance sheets are maintained from which operating profit and the rate of return on capital can be derived.

The Establishment is the level at which the accounting data required to measure production is available (principal inputs, revenues, salaries and wages).The establishment, as a statistical unit, is defined as the most homogeneous unit of production for which the business maintains accounting records from which it is possible to assemble all the data elements required to compile the full structure of the gross value of production (total sales or shipments, and inventories), the cost of materials and services, and labour and capital used in production.

The Location (the bottom of the hierarchy) requires only the number of employees for delineation. This unit is used only by the monthly survey of retail sales and inventories. The location, as a statistical unit, is defined as a producing unit at a single geographical location at which or from which economic activity is conducted and for which, at a minimum, employment data are available.

3.2 Retail-Specific Surveys
The Annual Retail Chain Survey measures, on an annual basis, the operating and financial characteristics of domiciled retail corporate chains and department stores. A "retail store chain" is defined as an organization operating four or more outlets in the same industry class under the same legal ownership at any time during the survey year. The independent stores could be both franchise and truly independent businesses. A "franchise" is part of a group of stores that sell the same products and operate similarly, but each franchise is independently owned. An "independent" store generally operates less than four locations.

3.3 Data Aggregation
The various data sources provide data at differing degrees of aggregation. The starting point for the information is the detailed NAICS classification. Because of the constraints of data confidentiality and survey samples, the detailed industries have been aggregated in some presentations into trade groups or special aggregates. The table below shows these aggregates defined in terms of the most detailed NAICS codes. In some cases, surveys such as LFS are only coded at a more aggregated level requiring minor adjustments to the classification.

For the analysis of the WES survey, two aggregations, the traditional total retail and one excluding supermarkets are used. The exact definitions are:

(1) NAICS (441-448, 451-454)
(2) NAICS (441-444, 4453, 446-448, 451-454).