When relevant to the determination of the value of property, a witness may take into account as a basis for his opinion the value of the property or property interest being valued as indicated by the value of the land together with the cost of replacing or reproducing the existing improvements thereon, if the improvements enhance the value of the property or property interest for its highest and best use, less whatever depreciation or obsolescence the improvements have suffered.

(Added by Stats. 1965, Ch. 1151.)