(a) Notwithstanding any provision of this part, including, but not limited to, subdivision (e) of Section 22664, and except as provided in subdivisions (b) and (c), the annual allowance payable on the effective date of this section to a retired member, an option beneficiary, or a surviving spouse receiving an allowance pursuant to either Section 23805 or 23855 shall not be less than the amount identified in the following schedule for the number of years of the member’s credited service under the Defined Benefit Program at the time of the member’s retirement, disability, or death, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, after the application of all allowances and allowance increases authorized by this part, including those specified in Sections 24412 and 24415, as those sections read on December 31, 2000, and excluding increases authorized by Section 24410.7 and annuities payable from the accumulated annuity deposit contributions or the accumulated tax-sheltered annuity contributions:

(b) Notwithstanding subdivision (a), the amount identified in the schedule in subdivision (a) shall be reduced:

1. (1) By 50 percent for a beneficiary receiving an allowance under Option 3 or Option 7.
2. (2) By one-third for an option beneficiary receiving an allowance under Option 4 after the death of the member or for a member receiving an allowance under Option 4 after the death of the option beneficiary.
3. (3) By 50 percent for an option beneficiary receiving an allowance under Option 5 after the death of the member or for a member receiving an allowance under Option 5 after the death of the option beneficiary.
4. (4) By a percentage equal to 100 percent minus the percentage of the member’s modified allowance received by the option beneficiary for each option beneficiary receiving an allowance under Option 8.
5. (5) By 60 percent for a surviving spouse receiving an allowance pursuant to subdivision (a) of Section 23805.
6. (6) By 50 percent for a surviving spouse receiving an allowance pursuant to subdivision (c) of Section 23805 or Section 23855.

(c) A benefit shall be paid pursuant to this section if both of the following apply:

1. (1) The retired member, the option beneficiary, or the surviving spouse had an allowance payable on January 1, 2000, and was not eligible to receive a benefit pursuant to Section 24410.5.

2. (2) The retired member or the member whose service was the basis of the allowance payable to the option beneficiary or surviving spouse was one of the following:

   1. (A) A member who retired prior to the age of 55 years, provided the minimum allowance specified in subdivision (a) shall be reduced to an amount equal to that minimum allowance multiplied by the ratio of the percentage of final compensation per year of credited service on which the member’s initial allowance was based to 1.4.
   2. (B) A member who was paid a retirement allowance pursuant to Section 24211, 24212, or 24213, if the member’s credited service, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, was less than 20 years but whose projected service to normal retirement age, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, was equal to or greater than 20 years, provided that the minimum allowance payable shall be based on 20 years of credited service.
   3. (C) A member who retired as an inactive member.
   4. (D) A member who retired prior to March 21, 1974, with 19.5 years or more of credited service, provided that the minimum allowance payable shall be based on 20 years of credited service.
   5. (E) A member who retired on or after March 21, 1974, and prior to January 1, 2000, and whose credited service, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, was less than 20 years, but whose credited service, excluding service credited pursuant to Sections 22714, 22715, and 22826, but including service credited pursuant to Section 22717, was equal to or greater than 20 years, provided that the minimum allowance payable shall be based on 20 years of credited service.
   6. (F) A member whose credited service, excluding service credited pursuant to Sections 22714, 22715, and 22826, but including credited service that a court has ordered be awarded to the member’s nonmember spouse pursuant to Section 22652, equaled at least 20 years, provided that the amount payable to the member pursuant to this section shall be based on the amount of service credited to the member, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, and the amount awarded to the nonmember spouse, and further provided that the minimum allowance specified in subdivision (a) shall be reduced to an amount equal to that minimum allowance multiplied by the ratio of (i) the amount of service credited to the member, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, to (ii) the sum of the amount of service credited to the member, excluding service credited pursuant to Sections 22714, 22715, 22717, and 22826, and the amount awarded to the nonmember spouse.