Double counting
From ACT Wiki
1. Accounting.
An error where a transaction or item is counted more than once.
2. Economics.
The error of counting the value of a nation's or other entity's goods more than once in calculating total production levels or other activity levels.
This can happen when products are produced in stages, through specialised channels of production and intermediate goods are used to produce the final products.
If the values of the intermediate stages are added together, without subtracting expenditure incurred during the production process, the error of double counting will occur.
3. Other errors.
More generally, any similar error in other contexts.
