Which principle of value indicates that a part of a property contributes to its overall value or detracts when absent?

The principle of value that indicates how a part of a property contributes to its overall value or detracts when absent is known as the principle of Contribution. This principle emphasizes that the value of a component or feature of a property is determined by the amount it adds to the overall property value, or conversely, how its absence can lower the property's value.

For example, if a home has a swimming pool, the pool can enhance the value of the property. If the pool were removed, the value of the property might decrease due to the loss of this amenity. This principle is fundamental when assessing real estate, as it guides appraisers and investors in understanding how each element of a property plays a role in its total value.

Understanding the principle of Contribution allows stakeholders to make informed decisions when buying, selling, or improving properties. It also highlights the necessity of evaluating individual components, as not all features add equal value and some may even detract from a property's worth if they do not align with market demand.