Answer:
Total number of years remaining for employees = 3 + 4 + 5 + 6 + 6 = 24 years.
Projected benefit of $88,560.
Year Annual Amortization
2020 88,560 * 5/24 $18,450
2021 88,560 * 5/24 $18,450
2022 88,560 * 5/24 $18,450
2023 88,560 * 4/24 $14,760
2024 88,560 * 3/24 $11,070
2025 88,560 * 2/24 $7,380
Total $88,560
Every year the projected benefit is amortized by the number of employees still working divided by the total number of years for all the employees.