ยง 5001. Interest to verdict, report or decision. (a) Actions in which recoverable. Interest shall be recovered upon a sum awarded because of a breach of performance of a contract, or because of an act or omission depriving or otherwise interfering with title to, or possession or enjoyment of, property, except that in an action of an equitable nature, interest and the rate and date from which it shall be computed shall be in the court's discretion. (b) Date from which computed. Interest shall be computed from the earliest ascertainable date the cause of action existed, except that interest upon damages incurred thereafter shall be computed from the date incurred. Where such damages were incurred at various times, interest shall be computed upon each item from the date it was incurred or upon all of the damages from a single reasonable intermediate date. (c) Specifying date; computing interest. The date from which interest is to be computed shall be specified in the verdict, report or decision. If a jury is discharged without specifying the date, the court upon motion shall fix the date, except that where the date is certain and not in dispute, the date may be fixed by the clerk of the court upon affidavit. The amount of interest shall be computed by the clerk of the court, to the date the verdict was rendered or the report or decision was made, and included in the total sum awarded.