Section 60K. In any action for malpractice, negligence, error, omission, mistake or unauthorized rendering of professional services, other than actions brought under section 2 of chapter 229, against a provider of health care, in which a verdict is rendered or a finding made or an order for judgment made for pecuniary damages for personal injuries to the plaintiff or for consequential damages, there shall be added by the clerk of the court to the amount of damages interest thereon, at a rate to be determined as set forth below rather than the rate specified in section 6B of chapter 231, from the date of the commencement of the action even though such interest brings the amount of the verdict or finding beyond the maximum liability imposed by law. For all actions commenced after the effective date of this act, the rate of interest to be applied by the clerk shall be at a rate equal to the weekly average 1–year constant maturity Treasury yield plus 2 per cent, as published by the Board of Governors of the Federal Reserve System for the calendar week preceding the date of judgment. At no point shall the rate of interest established by this section exceed the rate of interest set forth in said section 6B of chapter 231.