Demand is an estimate of the amount of goods and services required by a region. The value is calculated using industry purchases across the nation, measured in terms of sales. Industry wages, taxes, and other value-added payments are indirectly part of the demand through the production of the supplying industry. It is not possible to know the proportion in which demand should be broken out into categories such as wages, taxes, etc., but it is assumed that demand includes those categories.
See also: Sales, How Do Demand and Sales Differ?