After the adjustment prescribed in section 81-2035 is made, any annuity paid pursuant to sections 81-2014 to 81-2034 to any officer or surviving spouse qualified to receive such payment shall be adjusted on May 27, 1989, to reflect changes in the cost of living and wage levels which have occurred subsequent to the date of retirement up to an annuity total amount equal to five thousand nine hundred eighty dollars for a one-member family unit. For each additional member of the family unit the amount shall be increased by two thousand forty dollars. The annuity shall be adjusted to reflect any changes in the family unit when the change occurs. A change in the family unit after retirement occurs (1) upon the death of the officer, (2) upon the death of the spouse or a dependent child, (3) upon the birth of a dependent child, (4) upon the divorce of the officer and his or her spouse, (5) when the officer no longer provides support for a dependent child, and (6) when a dependent child becomes nineteen years of age. Each officer or surviving spouse whose annuity is adjusted pursuant to this section shall file an annual report with the retirement system, on a form prescribed by the Public Employees Retirement Board, to verify the size of the family unit. For purposes of this section, family unit shall include the officer, his or her spouse at the time of retirement, the officer's legal dependent children under nineteen years of age, and the officer's dependent handicapped children.