Notwithstanding the provisions of Sections 22C and 22D of Chapter 32 of the general laws, a retirement system may, upon the occurrence of an extraordinary market event, extend its funding schedule by up to 20 years for losses incurred in such extraordinary market event.  An extraordinary market event shall be determined by the state actuary but such determination shall not be made in the absence of a market loss of less than ten percent.  When the annual amount, determined by the actuary pursuant to section 22 of Chapter 32, to be paid for any retirement system is greater than seven percent more than the amount paid the prior year, the amount paid by any government unit within that retirement system shall not be increased greater than seven percent.  Any difference between the amount determined pursuant to said section 22 and seven percent shall be added to the unfunded pension liability of the system and shall be funded over the remaining years in the funding schedule.