Except as provided by Section 304.105 or 304.108, prejudgment interest accrues on the amount of a judgment during the period beginning on the earlier of the 180th day after the date the defendant receives written notice of a claim or the date the suit is filed and ending on the day preceding the date judgment is rendered. Prejudgment interest is computed as simple interest and does not compound.
Tex. Fin. Code § 304.104