The prior statute provided: 'If, at the time of retirement, he [a district judge] has attained the age of at least 70 years and he has served for 15 years as such judge, or as such judge and as judge of a court of record, he shall receive for the remainder of his life, one-half the compensation allotted to the office.' The 1967 amendment provided: '* * * He shall receive for the remainder of his life, one-half of the compensation allotted for the office at the time of his retirement.' The 1969 amendment provided: '* * * He shall receive for the remainder of his life, one-half the compensation allotted to the office at the time of his retirement or on July 1, 1967, whichever is greater.' Each of the Ps involved has served as a judge of the district court for the requisite time to qualify for retirement compensation. Each has retired according to law, and in all cases where there was a balance of the term of the retired judge yet to be served, he has filed in writing a waiver of full payment for the balance of such term. In 1971, each of the judges was receiving retirement compensation in the amount of $11,000 per annum. The legislature in that year increased the compensation allotted to the office of district judge from $22,000 to $29,000 per annum. Under the pre-1967 formula, the retirement compensation of these judges would have increased to $14,500. Under the 1967 and 1969 formulae they continued to receive $11,000 per annum. Each P made a written demand for an increase in compensation based on the fact that they were entitled to one-half the compensation allotted to the office, not one-half the compensation allotted to the office at the time of retirement. Ds refused. Ps commenced these actions for a declaratory judgment that the amendment of the statute was unconstitutional as to them on the ground that they had contractual rights which were impaired by the amendments. The trial court held that 4 judges had contractual rights to retirement benefits based on the statutes as they existed at the time of their retirement and that the amendments were unconstitutional as to them. One judge had no such rights since he retired after the enactment of the amendments and therefore there was no impairment of his contractual rights. One judge was entitled to the retirement benefits existing at the time he submitted his request for retirement, even though the retirement became effective after the 1967 amendment of the statute was enacted. Ds appealed.