What is the test for determining a reasonable attorney fee under a contingency agreement?

"While the amount to be awarded as attorney fees is a matter committed to the court's discretion [citation], courts have developed general rules to guide the exercise of that discretion in determining a reasonable fee. [Citation.]" (People ex rel. Dept. of Transportation v. Yuki (1995) 31 Cal.App.4th 1754, 1767, 37 Cal.Rptr.2d 616.) "A trial court may not determine a 'reasonable' attorney fee solely by reference to the amount due under a contingency agreement. [Citations.] However, the court may consider the contingent nature of the fee agreement as one factor in determining a reasonable fee. Other factors to be considered by the court, where appropriate, include: the novelty and difficulty of the questions involved and the skill required to perform the legal services properly; the likelihood that the acceptance of this particular employment would preclude other employment by the attorneys; the amount involved and the results obtained; the time limitations imposed by the clients or by the circumstances of the case; the nature and length of the professional relationship with the client; the experience, reputation, and ability of the attorneys who performed the services; the time and labor required of the attorneys; and the informed consent of the client to the fee agreement. [Citations.]" (Id. at pp. 1770-1771, 37 Cal.Rptr.2d 616, italics in original.) Based on the record, we cannot say the trial court abused its discretion in its award of attorneys' fees.