“In an action for professional negligence, the total contingent fee for the plaintiff’s attorney or attorneys shall not exceed the following amounts, exclusive of litigation expenses:
A. Thirty-three and one-third percent of the first $100,000 of the sum recovered; [PL 1985, c. 804, §§ 16, 22 (NEW).]
B. Twenty-five percent of the next $100,000 of the sum recovered; and [PL 1985, c. 804, §§ 16, 22 (NEW).]
C. Twenty percent of any amount over $200,000 of the sum recovered.” [MRS § 2961]