This is the high-level description of what the money will be spent on in each department. If a department spends money outside the scope of the ‘ambit’ approved by Parliament, then that spending is unauthorised and therefore illegal. In such circumstances a department will require a Statement of Excess to provide retrospective approval for the spending.

These cover net spending, subject to the limits set out in the Spending Review process, in areas of activity that departments can generally forecast and over which they are therefore expected to exercise control. In each annual Estimate, the DELs are divided into two sub-categories:

• Resource DEL, or current ‘day-to-day' spending: this includes, for example, costs for staff, purchasing goods and services, rents, maintenance and other administrative costs, depreciation and the sale of assets.

• Capital DEL, or investment spending: this includes capital grants, loans, and the purchase, disposal or improvement of major assets.

This covers net spending in areas that are less predictable and therefore more difficult for departments to forecast and control:

• Resource AME: this includes benefits, state pensions, and other welfare costs, as well as provision for liabilities.

• Capital AME: this includes areas such as student loans.

• Generally, departments cannot switch funds from DEL to AME, or from resource to capital spending categories, once the Estimate has been approved. However, within each category, a breakdown of proposed spending is provided, and this does not bind the government. Here, the government can vire money from one heading area to another, provided that neither the ambit nor the overall spending limit is breached.