Answer:
Economic or Useful Life
Step-by-step explanation:
The time period that the asset is in the business, it is expected to generate economic benefits for the company.
This time period is usually known as the economic life/useful life of the asset and may be shorter or longer than its legal life.
Note : Legal life of an asset is its period of operation granted by a law especially for intangible assets. Examples are trademark and copyrights.